[Federal Register Volume 68, Number 154 (Monday, August 11, 2003)]
[Rules and Regulations]
[Pages 47485-47497]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-20025]


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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. 03-15277]
RIN 2127-AH16


Federal Motor Vehicle Safety Standards: Heavy Vehicle Antilock 
Brake System (ABS) Performance Requirement

AGENCY: National Highway Traffic Safety Administration (NHTSA), 
Department of Transportation (DOT).

ACTION: Final rule.

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SUMMARY: In March 1995, NHTSA published a final rule amending the 
hydraulic and air brake standards to require medium and heavy vehicles 
(e.g., truck tractors, trailers, single unit trucks, and buses) to be 
equipped with antilock brake systems (ABS) to improve the directional 
stability and control of these vehicles during braking. We supplemented 
the ABS requirements for truck tractors with a braking-in-a-curve 
performance test. The braking-in-a-curve test was not applied to 
single-unit trucks or buses or to air-braked trailers because we had 
performed only limited testing of ABS-equipped single-unit vehicles. We 
stated that we would continue research on dynamic performance tests for 
single-unit trucks, buses, and trailers, and would consider applying 
performance test requirements to these vehicles in the future.
    After issuing the final rule, we tested several ABS-equipped 
single-unit trucks and buses equipped with both hydraulic and air 
brakes. Our testing and research indicated that the braking-in-a-curve 
performance test requirement is practicable for those vehicles. 
Accordingly, in December 1999, we proposed applying the braking-in-a-
curve requirements to them to complement both the ABS equipment 
requirements and stopping distance requirements. This final rule 
extends application of the braking-in-a-curve dynamic performance test 
requirement to single-unit trucks and buses that are required to be 
equipped with ABS.

DATES: The amendments made in this rule are effective October 10, 2003. 
If you wish to petition for reconsideration of this rule, your petition 
must be received by September 25, 2003.

ADDRESSES: Any petitions for reconsideration should refer to the docket 
and notice number of this notice and be submitted to: Administrator, 
National Highway Traffic Safety Administration, 400 Seventh Street, 
SW., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: For non-legal issues, you may call Mr. 
Jeff Woods, Safety Standards Engineer, Office of Crash Avoidance 
Standards, Vehicle Dynamics Division at (202) 366-2720, and fax him at 
(202) 493-2739.
    For legal issues, you may call: Mr. Otto Matheke, Attorney-Advisor, 
Office of the Chief Counsel at (202) 366-2992, and fax him at (202) 
366-3820.
    You may send mail to both of these officials at National Highway 
Traffic Safety Administration, 400 Seventh St., SW., Washington, DC, 
20590.

SUPPLEMENTARY INFORMATION: 

I. Background
II. Single-Unit Truck & Bus ABS Performance Testing
III. Notice of Proposed Rulemaking
IV. Public Comments
V. Final Rule
VI. Pre-selection of Compliance Option
VII. Effective Date
VIII. Rulemaking Analyses and Notices

I. Background

    On December 18, 1991, the Intermodal Surface Transportation 
Efficiency Act (ISTEA or Act), Public Law 102-240 was signed by 
President George H. Bush and became law. Section 4012 of the Act 
directed the Secretary of Transportation to initiate rulemaking for 
improving the braking performance of new commercial motor vehicles--
defined by ISTEA as those with a GVWR of over 26,000 pounds (lbs.)--
including truck tractors, trailers, and dollies. The Act directed that 
in that rulemaking, the agency examine antilock brake systems (ABS), 
means of improving brake compatibility, and methods of ensuring the 
effectiveness of brake timing. In response to that congressional 
mandate, we published a final rule requiring ABS to be installed on 
hydraulic and air-braked medium and heavy vehicles on March 10, 1995 
(60 FR 13216) (hereinafter referred to as the stability and control 
final rule). For truck tractors only, the ABS requirements included a 
braking-in-a-curve performance test on a low-coefficient of friction 
surface. The test includes a full brake application in both the lightly 
loaded (bobtail) configuration and with the tractor loaded to its GVWR, 
the latter using an unbraked control trailer.
    Due to limited data and concerns regarding the braking-in-a-curve 
test, the March 1995 Final Rule did not apply the test to single-unit 
trucks, buses, or air-braked trailers. We stated, however, that we 
would continue research on dynamic performance tests for single-unit 
vehicles and would consider proposing to apply performance test 
requirements to those vehicles at a future time.\1\
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    \1\ The agency published two companion final rules on the same 
day, one to reinstate stopping distance requirements for air-braked 
medium and heavy vehicles (60 FR 13286) and another to implement 
stopping distance requirements for hydraulic-braked medium and heavy 
vehicles (60 FR 13297). The cost/benefit information used for the 
three final rules was based on NHTSA's Final Assessment, Final 
Rules, FMVSS Nos. 105 & 121, Stability and Control During Braking 
Requirements and Reinstatement of Stopping Distance Requirements for 
Medium and Heavy Vehicles, published in February, 1995.
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II. Single-Unit Truck and Bus ABS Performance Testing

    We conducted ABS testing of single-unit trucks and buses in 1996 
and 1997 at our Vehicle Research and Test Center (VRTC) in East 
Liberty, OH.\2\ Five air-

[[Page 47486]]

braked straight trucks and two hydraulic-braked buses, all equipped 
with ABS, were used in the tests to aid in determining if the braking-
in-a-curve performance test for tractors should be applied to single-
unit vehicles. The vehicles were subjected to all the requirements of 
Standards No. 105 and No. 121, including the braking-in-a-curve 
performance tests.
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    \2\ DOT HS 808941, Single Unit Truck and Bus ABS Braking-In-A-
Curve Performance Testing, February 1999.
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    The braking-in-a-curve tests began with the determination of a 
maximum drive-through speed, followed by the determination of the 
maximum brake-through speed. As defined in Standard No.121, ``maximum 
drive-through speed'' is the fastest constant speed that a vehicle can 
be driven through at least 200 feet of curve arc length without 
departing the lane. ``Maximum brake-through speed'' is defined as the 
fastest speed at which a full brake application can be made while the 
vehicle is in the curve, without the vehicle departing the lane. 
Determination of the maximum brake-through speed provided data on the 
potential margin of compliance or non-compliance for the test vehicles.
    In the agency's testing, both trucks and school buses were tested 
in loaded-to-GVWR and lightly loaded conditions. The trucks were ABS 
equipped chassis-cabs without bodies or equipment that would normally 
be installed by a second-stage manufacturer. However, to simulate the 
lightly loaded condition of completed vehicles, a 2,500 lb load frame 
with an integrated roll bar was installed on the chassis cabs. Trucks 
tested in the loaded-to-GVWR condition were weighted to their GVWRs, 
with the axle loads in proportion to their GAWRs. Two ABS equipped 
school buses were also tested in loaded-to-GVWR and lightly loaded 
conditions. The loaded-to-GVWR tests on the school buses were conducted 
with sand bags placed on the floor and seats so the total vehicle 
weight was equal to its GVWR, with axle loads in proportion to their 
GAWRs.
    The braking-in-a-curve tests were conducted on a low friction 
wetted surface. The test curve had a 12-foot-wide lane with a 500-foot 
radius of curvature (marked from the center of the lane). Traffic cones 
were placed on both sides of the lane at 20-foot intervals. The surface 
had a cross slope of one percent and approximately zero longitudinal 
slope. The peak coefficient of friction (PFC) of the surface during the 
time of the testing ranged from 0.34 to 0.41. The effect of the cross 
slope was such that the test condition was considered to be worst case, 
since it may not be possible to conduct all road testing on a 
completely level road surface, due to variability and water run-off 
design requirements. The lower end of the PFC range was also considered 
to be a worst-case test condition.
    The results of the testing at VRTC indicated that the braking-in-a-
curve test is practicable, repeatable, and safe for single unit 
vehicles. Six of the seven vehicles tested met the performance 
requirements now in effect for tractors, i.e., they stayed in the lane 
in at least three out of four stops when subjected to maximum braking 
at 75 percent of the maximum drive-through speed. In fact, these six 
vehicles remained in the lane during all four stops at 75 percent of 
the drive-through speed, all with a large margin of compliance.

III. Notice of Proposed Rulemaking

    On December 21, 1999, the agency published a notice of proposed 
rulemaking in the Federal Register (64 FR 71377) containing the 
agency's proposal for a braking-in-a-curve test for single-unit trucks 
and buses. NHTSA proposed that the braking-in-a-curve test be conducted 
in two different conditions: with the vehicle lightly loaded, and with 
the vehicle loaded-to-GVWR. The agency proposal also specified the same 
road test geometry now in effect for tractors, namely a 12-foot-wide 
lane with a 500-foot radius measured at the center of the lane with the 
test surface having a peak friction coefficient (PFC) of 0.5. The 
proposal also specified that the test speed is 75 percent of the 
maximum drive-through speed or 30 mph, whichever is lower. The brake 
pedal force specification proposed in the notice called for a pressure 
of 150 pounds to be achieved at the brake pedal within 0.2 seconds from 
the initial application and maintained for the duration of the stop. 
The proposal specified that the brake temperature at the time of 
testing is to be between 150 and 200[deg] F and the test performed with 
the transmission in neutral or the clutch pedal depressed. Finally, the 
agency proposal specified that in 3 of 4 consecutive stops, the test 
vehicle is to remain in the 12 foot wide marked lane when tested in 
both the lightly loaded condition and when loaded-to-GVWR in proportion 
to each GAWR.
    Since the braking-in-a-curve test is one brake test in a test 
sequence, the agency proposed that the braking-in-a-curve test for air-
braked single-unit trucks and buses be conducted immediately after the 
burnish procedure as indicated in Table I of Standard No. 121, with the 
loaded-to-GVWR tests followed by the lightly loaded tests. We also 
proposed that the braking-in-a-curve test for hydraulic-braked single-
unit trucks and buses be conducted immediately after the post-burnish 
brake adjustment in S7.4.2.2, with the loaded-to-GVWR tests followed by 
the lightly loaded tests.
    In order to provide manufacturers with sufficient lead time to 
comply with the proposed requirements, the proposal indicated that the 
effective date for the braking-in-a-curve test requirements, for both 
air and hydraulic-braked single unit trucks and buses, be two years 
after publication of the final rule in the Federal Register.

IV. Public Comments

    NHTSA received comments about its proposal from vehicle and brake 
manufacturers as well as safety and trade groups. Three vehicle 
manufacturers, DaimlerChrysler Corporation (DaimlerChrysler), Ford 
Motor Company (Ford) and Mitsubishi Motors R&D of America Incorporated 
(Mitsubishi), submitted comments. Comments were also received from 
Haldex Brake Products Corporation (Haldex), Bendix Commercial Vehicle 
Systems (BCVS) and Bosch Braking Systems Corporation (Bosch). Several 
trade associations, National Truck Equipment Association (NTEA), Heavy 
Duty Brake Manufacturers Council (HDBMC), American Trucking 
Associations (ATA) and Truck Manufacturers Association (TMA), offered 
their views. One safety group, Advocates for Highway Safety 
(Advocates), submitted comments as well.
    With the exception of TMA and NTEA, the commenters generally 
supported the agency proposal. However, many of the commenters argued 
that requiring that the braking-in-a-curve test be run in both the 
loaded-to-GVWR and lightly loaded conditions was unnecessary and that 
the lightly loaded test alone was sufficient. In addition, a number of 
commenters indicated dissatisfaction with the proposed test sequence 
and some of the proposed test conditions. Other commenters indicated 
their belief that the agency's proposal underestimated the compliance 
burdens that the proposal, if adopted, would impose on final stage 
manufacturers and alterers.
    One commenter addressed what it believed to be shortcomings in the 
configuration of the test curve. Advocates stated that the proposed 
test configuration--a zero longitudinal slope, 500-foot continuous 
curve radius, 12-foot wide lane and one percent side slope--does not 
approach worst-case real-world operating condition. In addition to 
criticizing the severity of the test, Advocates viewed the proposed 
test as not sufficiently demanding and

[[Page 47487]]

indicated that few vehicles equipped with ABS would fail the proposed 
test.
    DaimlerChrysler disagreed with the proposed requirement that ``no 
part'' of the test vehicle leave the marked lane of the braking curve 
during a stop. Instead, DaimlerChrysler requested that this requirement 
be changed so that a vehicle would comply if no part of any point of 
contact of any tire left the lane during the stop. The company noted 
that the agency proposal did not clearly indicate how any departure of 
any part of the vehicle from the traveled lane would be detected. 
DaimlerChrysler further indicated that vehicles with large rear 
overhang would be placed at a severe disadvantage since any lateral 
movement of the rear wheels would result in the rear of a longer 
vehicle moving closer to the outside of the lane. DaimlerChrysler also 
requested that NHTSA delete the specification that the braking-in-a-
curve test be conducted on a wet surface. In DaimlerChrysler's view, 
the requirement that the surface be wet is unnecessary. In the 
company's view, it is immaterial whether the test surface is dry or wet 
if the surface has the proper coefficient of friction (PFC).
    The comments submitted by vehicle manufacturers and trade groups 
were nearly unanimous in their disapproval of the proposed requirement 
that testing be conducted with vehicles in both a lightly loaded 
condition and a loaded-to-GVWR condition. HDBMC stated that many 
single-unit trucks and buses have already been tested for braking-in-a-
curve performance and that, with regard to loading condition, the 
worst-case condition is when the vehicle is lightest. HDBMC also stated 
that in the case of testing in the loaded-to-GVWR condition, it 
recommends that the center-of-gravity height for the ballast should be 
not more than 32 inches above the frame rails. Haldex and HDBMC also 
recommended that the 32-inch load height for single-unit trucks be 
specified for 60-mph straight-line stopping distance tests as well.
    BCVS advocated deletion of the fully-loaded braking-in-a-curve test 
for the following reasons: A lightly-loaded test condition is the most 
severe condition; the SAE recommended practice (RP) J1626 ``Braking 
Stability and Control Performance Test Procedures for Air and Hydraulic 
Brake Equipped Trucks, Truck-Tractors and Buses' specifies that the 
braking-in-a-curve performance test be conducted in the lightly-loaded 
condition with the loaded-to-GVWR condition optional; loading the 
vehicle increases the risk of rollover; and determining an appropriate 
loading specification for the variety of vehicle configurations and 
body forms would be difficult. BCVS further stated that if NHTSA 
believes that the fully-loaded braking-in-a-curve test is essential, 
then the load center-of-gravity height should be established at a 
height that is not likely to lead to vehicle rollover. Concerns about 
vehicle rollover apparently also prompted BCVS to suggest that the 
allowance of 1,000 lbs. for a rollbar, and 500 lbs. for driver and 
instrumentation, which was proposed in the NPRM for the lightly-loaded 
braking-in-a-curve test for single-unit trucks and buses, be applied to 
other lightly-loaded road tests in FMVSS No. 121.\3\
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    \3\ NHTSA has published a final rule (66 FR 64154) amending 
FMVSS No. 121 by incorporating the 1,000 lbs. rollbar provision.
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    Ford stated that it believes there is no useful information to be 
obtained from conducting the braking-in-a-curve test with the vehicle 
loaded-to-GVWR. Ford cited the fact that the SAE Truck and Bus Vehicle 
Deceleration and Stability Subcommittee found that 29 out of 31 single-
unit vehicles tested in the braking-in-a-curve test the lightly-loaded 
test condition performed the same or worse than when tested in the 
loaded-to-GVWR test condition. Ford states that the two vehicles that 
performed better in the loaded-to-GVWR test condition were heavier-duty 
trucks and had sufficient margins of compliance in both loading 
conditions.
    TMA stated that because of safety concerns, NHTSA should reconsider 
its decision to require the braking-in-a-curve test in the loaded-to-
GVWR test condition. TMA believes that a loaded-to-GVWR vehicle could 
slide off the low coefficient test surface of the 500-foot radius curve 
onto a higher coefficient of friction surface and then rollover. TMA 
cited NHTSA statements in the NPRM that the NHTSA tests involving 
vehicles with a load at a high center of gravity height caused an 
unsettling feeling [to the test driver] with regard roll stability. TMA 
presented data to support its view that testing in the loaded-to-GVWR 
condition is less stringent than testing in the lightly-loaded 
condition. TMA concluded that testing in the loaded-to-GVWR condition 
provides no additional confirmation of vehicle performance, presents a 
significant safety risk of vehicle rollover, and would increase test 
burdens without any measurable benefit to vehicle safety.
    In addition to advocating removal of the requirement that vehicles 
be tested in a loaded-to-GVWR condition, a number of commenters 
indicated that the proposed test sequence be changed.
    To reduce costs associated with loading and unloading test 
vehicles, Bosch requested that the braking-in-a-curve test be performed 
following the loaded-to-GVWR parking brake test, with the loaded-to-
GVWR braking-in-a-curve test followed by the lightly loaded braking-in-
a-curve test, for both hydraulic- and air-braked single-unit vehicles. 
Bosch also stated that it appeared that the agency had not considered 
the costs incurred by different phases of the test sequence requiring 
loading and unloading of the test vehicle. Bosch requested that the 
test sequence be changed to eliminate the requirement that empty 
vehicles be loaded solely for the purpose of conducting the braking-in-
a-curve test after brake burnishing. Ford requested that if the agency 
decided to drop the loaded-to-GVWR braking-in-a-curve test, the test 
sequence be changed so that burnish and loaded-to-GVWR straight-line 
stops be conducted first, followed by braking-in-a-curve tests in the 
lightly-loaded condition, followed by lightly-loaded straight-line 
stops. In Ford's view, this sequence would eliminate one loading and 
unloading cycle and improve test efficiency.
    One manufacturer, Mitsubishi, commented that the requirements 
proposed for the force and timing of brake pedal applications during 
the braking-in-a-curve test are too stringent. The proposal specified 
that a brake pedal force of 150 lbs. be achieved within 0.2 second from 
the initial application of force to the brake control (brake pedal) and 
that this minimum force be maintained for the duration of the stop. 
Mitsubishi believes that this application time would be difficult to 
achieve. The company provided test data from tests conducted on single 
unit trucks showing that test drivers could achieve 150 lbs. of pedal 
force within 0.2 seconds in only three out of 10 sample stops.
    TMA and NTEA criticized our proposal as imposing significant test 
burdens and costs on small businesses beyond what those entities should 
reasonably be expected to bear. These commenters are concerned that 
final stage manufacturers and alterers may not be able to rely on the 
certification of an incomplete vehicle manufacturer to the extent 
portrayed by the agency in proposing the new requirements, particularly 
since many trucks are configured for highly specialized applications. 
Moreover, TMA argued that since NHTSA is proposing performance 
requirements for all classes of vehicles, it should consider removing 
the existing ABS equipment requirements. TMA stated these equipment 
requirements are unduly restrictive and may impede

[[Page 47488]]

development of improved ABS systems. NTEA stated that the proposal 
should be abandoned on the basis that there are no additional benefits 
attained by adding the proposed test procedure.
    In regard to costs, TMA argued that in preparing the proposal, 
NHTSA tested only the most common two- and three-axle truck 
configurations (i.e., 4 x 2 and 6 x 4), and has not adequately 
addressed the problems posed by other axle configurations. As 
aftermarket axles are often added to incomplete vehicles--which can 
cause a vehicle to fall outside of the Incomplete Vehicle Document 
(IVD) parameters specified by the incomplete vehicle manufacturer--
final stage manufacturers will bear additional responsibility for 
certification. TMA stated that low-volume, special configurations may 
need to be excluded from this portion of the standard, and believes 
that it is premature to conclude that the proposal is practicable for 
all single-unit trucks and buses. TMA also believes the agency has 
significantly underestimated the cost of performing stand-alone 
braking-in-a-curve tests on previously certified vehicles. TMA stated 
that stand-alone testing will require shipping vehicles to a test site, 
installation of new brake system parts, burnishing, loading and 
unloading, charges for facilities, drivers, mechanics and test 
engineers as well as instrumentation support and reporting. The 
organization estimated that stand-alone braking-in-a-curve testing 
costs will average between $4,500 and $6,000 per test and a full FMVSS 
No. 105 or 121 certification will cost $10,000 to $13,000.
    NTEA also believes that pass-through certification requirements 
supplied by incomplete vehicle manufacturers will be so restrictive 
that pass-through certification will not be available and that small 
companies would not have the means to conduct certification testing. 
NTEA stated that a final stage manufacturer could ensure compliance 
only through actual testing. In NTEA's view, the added cost of this 
testing will be prohibitive. Therefore, NTEA contends that final stage 
manufacturers would be compelled either to cease operations or choose 
not to test and risk a host of liabilities. NTEA further argues that 
the agency has repeatedly taken the position that alternatives to 
actual compliance testing, such as engineering analyses, computer 
simulations, or group testing through trade associations, may not 
suffice as evidence of the due care required for certification.
    DaimlerChrysler referred to what it believes to be errors in the 
agency proposed changes to FMVSS No. 105. The company stated that the 
proposed regulatory text deleted S7.8 from the list of test procedures 
and sequences, and inadvertently added S7.11. DaimlerChrysler also 
believes that the words ``except for vehicles with a GVWR greater than 
10,000 lbs.'' were inadvertently deleted from S7.5(b), and that the 
word ``must''--proposed in lieu of the current ``shall'' in S7--should 
be retained. DaimlerChrysler also noted that the word ``control'' was 
deleted from the phrase ``transmission selector control'' in S7 and 
recommended that the word ``control'' be retained. Finally, 
DaimlerChrysler indicated that while it prefers retaining the existing 
language for S5.7(b), which governs test speeds for each category of 
vehicle for the second effectiveness test, that the existing language 
of S5.7(b) is also incorrect

V. Final Rule

    This final rule adopts the amendments to FMVSS No. 105 and FMVSS 
No. 121 proposed in the December 21, 1999 NPRM with several 
modifications. First, because the agency agrees with those commenters 
who argued that the lightly loaded test condition is the most severe 
test of an ABS system in a braking-in-a-curve test, the final rule 
eliminates the proposed requirement that testing include braking runs 
by a vehicle in a loaded-to-GVWR condition. The final rule also 
modifies the proposed test sequence to reflect the elimination of the 
loaded-to-GVWR condition requirement and to simplify testing. We are 
also modifying the requirements for the full brake application used in 
the braking-in-a-curve test and making a number of corrections to the 
regulatory text.
    The most significant modification to the proposal is our decision 
to eliminate the requirement that the braking-in-a-curve test be 
performed with the test vehicle in a lightly loaded and heavily loaded 
configuration. The comments submitted in response to the NPRM favored 
elimination of the requirement that vehicles be tested in a loaded-to-
GVWR condition. These commenters argued that the brakes on a lightly 
loaded vehicle are generally much more likely to lock on a low friction 
surface than those on an identical vehicle with a heavy load.
    The agency's own testing and data submitted by TMA indicate that 
the lightly-loaded test condition has a lower margin of compliance than 
tests in the loaded-to-GVWR condition. In those few cases in which the 
loaded-to-GVWR test condition resulted in a lower margin of compliance, 
the margin of compliance was still quite large for the lightly-loaded 
condition. These tests and data demonstrate that the loaded-to-GVWR 
test offers little additional information about a vehicle's ABS 
performance beyond what can be shown by just using the lightly-loaded 
test.
    In addition, the agency agrees with the observations of several 
commenters that there is a risk of vehicle rollover while conducting 
the braking-in-a-curve test with a loaded-to-GVWR vehicle unless a low 
center-of-gravity loading scheme is required. Developing and 
implementing a uniform low center-of-gravity scheme for single-unit 
vehicles would be difficult given the large number of single-unit truck 
configurations. Use of a higher center-of-gravity load increases 
concerns about roll stability. During the maximum drive-through speed 
test, which determines the speed at which the braking-in-a-curve test 
is conducted, the test vehicle will depart from the test lane if the 
driver exceeds the maximum drive through speed of the vehicle for that 
road surface condition. If this occurs, the test vehicle may move 
laterally onto a wet asphalt surface with a higher coefficient of 
friction (PFC 0.8). In these conditions, a vehicle loaded so that it 
has a high center of gravity could become unstable and rollover. The 
HDBMC offered its view that the agency should specify a 32-inch center-
of-gravity height for any ballast added to create a loaded condition 
for any agency braking tests, including the proposed test. We note 
first that as the agency is not specifying that the braking in a curve 
test be performed in a loaded-to-GVWR condition, this eliminates 
HDBMC's concerns for that test.
    While the agency is not including the fully-loaded-to-GVWR braking-
in-a-curve test for single-unit vehicles in this final rule, it will 
keep this test requirement in FMVSS No. 121 for truck tractors. Reasons 
for keeping this requirement include the large variation in vehicle 
weight of unladen tractors (bobtail) to fully-loaded-to-GVWR tractors; 
the large contribution of the tractor in providing braking force when a 
loaded semi-trailer is coupled to the tractor; and the articulated 
configuration of the tractor and semitrailer that results in the 
trailer contributing to the lateral force on the tractor drive wheels 
during a braking-in-a-curve test. In addition, since loading a tractor 
to GVWR is accomplished by coupling a loaded control trailer to the 
tractor, the labor effort for loading and unloading is minimal compared 
to single-unit vehicles.
    This final rule also modifies the test sequence. We note that our 
proposed test sequence, which is already in effect for truck tractors, 
is based on several

[[Page 47489]]

factors. The braking-in-a-curve test is placed early in the sequence so 
re-running the required straight line tests need not be done if the 
vehicle does not pass the braking-in-a-curve test. In addition, placing 
the braking-in-a-curve test early in the sequence avoids performing the 
braking-in-a-curve test with tires that may have developed flat spots 
on non-ABS controlled wheels during other tests. Although these flat 
spots will not appear if all wheels of a vehicle are controlled by ABS, 
there is no requirement that vehicles be so equipped. NHTSA must assume 
that compliance testing may encompass vehicles that do not have ABS 
controlling all their wheels. However, placing the braking-in-a-curve 
test near the beginning of the test sequence when the vehicle has to be 
tested in a loaded-to-GVWR and lightly-loaded condition, requires that 
the vehicle be loaded, tested in the curve, unloaded, tested in the 
curve and then loaded again for straight line tests. Compared to 
tractors, where the loading and unloading involves attaching or 
uncoupling a trailer, the loading and unloading of vehicles is more 
time consuming, particularly for buses where weights have to be placed 
in each seating position.
    Our decision to require the braking-in-a-curve test for single unit 
vehicles only in the lightly loaded condition eliminates the need for 
loading and unloading for the braking-in-a-curve test. However, as some 
of the commenters observed, other changes to test sequences could 
reduce test burdens without compromising safety. Changing the FMVSS No. 
105 test sequence to perform the braking-in-a-curve after the lightly-
loaded parking brake test would reduce the unloading/loading and 
loading/unloading cycles in the entire test sequence from four to two. 
Changing the test sequence for single unit vehicles in FMVSS No. 121 so 
that the braking-in-a-curve test is performed after the loaded-to-GVWR 
parking brake tests would reduce the unloading/loading and loading/
unloading cycles from three to one. As these changes to the test 
sequences would reduce test burdens and not compromise safety, this 
final rule revises the test sequences in FMVSS No. 105 so the braking-
in-a-curve test is performed after the lightly loaded parking brake 
test and incorporates a test sequence for single unit vehicles in FMVSS 
No. 121 specifying that the braking-in-a-curve test is performed after 
the loaded-to-GVWR parking brake tests.
    One commenter, Mitsubishi, submitted data to support its argument 
that NHTSA's proposed specifications for the brake application used in 
the FMVSS No. 105 braking-in-a-curve test were too stringent. As 
indicated above, the company argued that our proposal that a brake 
pedal force of 150 lbs. be achieved within 0.2 second from the initial 
application of force would be impractical. Data from testing performed 
by Mitsubishi using test drivers in single unit trucks indicated that a 
pedal force of 150 lbs. was achieved in 0.2 seconds or less in only 
three out of ten stops. Mitsubishi suggested that a 0.5 second 
application time is more practicable.
    NHTSA agrees that it is difficult to reach the required application 
pressure within 0.2 second with a test driver. However, the agency 
believes that a 0.5 second application time is too slow. The Mitsubishi 
data show that the application time for the ten stops ranged from 0.18 
to 0.31 second. The data also show that the 150 lbs. threshold was 
exceeded significantly in every case within 0.5 second of the initial 
application. Our review of the Mitsubishi data indicates that a test 
driver is able to reach 150 lbs. of force within 0.3 second of the 
initial application. Accordingly, this final rule specifies that a full 
brake application for the braking-in-a-curve test consists of an 
application where 150 lbs. of force is applied to the brake control 
within 0.3 seconds of the initial application of force to the brake 
control.
    Finally, NHTSA is making a number of changes to the regulatory text 
to resolve errors and clarify the new requirements. As proposed in the 
NPRM, S5.1.7 of FMVSS No. 105 stated that the braking-in-a-curve test 
must be conducted at lightly-loaded vehicle weight plus up to 500 lbs. 
to allow for a test driver and instrumentation. However, S4 of FMVSS 
No. 105 already included a definition of lightly-loaded vehicle weight 
(for vehicles over 10,000 lbs. GVWR) with an allowance for 500 lbs. for 
the test driver and instrumentation. As the definition of ``lightly-
loaded'' already includes an allowance for the test driver and 
instrumentation, this final rule deletes the redundant language in 
S5.1.7. DaimlerChrysler's comments indicated that the agency 
inadvertently deleted S7.8 from the list of test procedures and 
sequences in FMVSS No. 105, and inadvertently added S7.11 to the list. 
NHTSA agrees and is correcting the errors in the final rule. To address 
other errors noted by DaimlerChrysler, the final rule inserts the 
phrase ``except for vehicles with a GVWR greater than 10,000 lbs.'' in 
S7.5(b), the words ``shall'' and ``control'' in S7, and in S5.7.(b) 
modifies the table or test speeds for each category of vehicle for the 
second effectiveness test.
    The agency is making other minor technical or clarifying changes 
based on its own review. The first sentence of S6.1.1 referencing 
lightly-loaded braking tests is also amended to include a reference to 
the braking-in-a-curve test for vehicles over 10,000 lbs. GVWR and 
S6.1.2, which identifies how the 500 lbs. of weight allowed for the 
test driver and instrumentation is to be placed in the vehicle, is also 
modified from the language of the proposal. The text of S6.9.2(a), 
which specifies the test surface for stopping distance tests in FMVSS 
No. 105, is also being revised to clarify that this specification does 
not include the stability and control while braking test in S6.9.2(b). 
S7 is revised in the final rule to accommodate the insertion of the 
stability and control test in S7.5(a), and references to S7.5 in the 
test procedure and sequence are being changed to S7.5(b). The final 
rule also deletes the proposed language of S5.3.6.2(a) of FMVSS No. 
121--indicating that the vehicle is to be loaded to its GVWR in 
proportion to its GAWRs --as this specification is already included in 
S6.1.1 under S6, Road Test Conditions.
    In limiting the modifications to its original proposal to those 
items described above, the agency is rejecting a number of changes 
suggested by the commenters. Advocates stated that the characteristics 
of the roadway specified for the braking-in-a-curve test do not 
approach worst-case operating conditions and that few vehicles properly 
equipped with ABS would fail the proposed braking-in-a-curve test. 
NHTSA disagrees that the braking-in-a-curve course is not demanding, 
since disabling the ABS on single-unit trucks and buses would likely 
result in these vehicles departing the lane during a full effort brake 
application. The agency believes that the proposed test configuration 
is sufficiently rigorous to evaluate the safety performance of ABS.
    DaimlerChrysler requested that compliance with the braking-in-a-
curve test be determined on the basis of whether any tire point-of-road 
contact leaves the test lane rather than any part of the vehicle 
leaving the roadway. The company argued that the latter measure is 
unclear and should not be applied to vehicles with large rear 
overhangs. NHTSA believes that the measure of compliance is clear as it 
stands and well understood to mean that in the plan view (view from the 
top looking down), no part of the vehicle shall pass outside of the 12-
foot lane during the stop. As currently specified in the FMVSS No.

[[Page 47490]]

121 test procedure, the test driver is instructed to start each 
braking-in-a-curve maneuver with the vehicle in the center of the lane. 
The test lane is marked with cones placed at 20-foot intervals that are 
tall enough to contact the body of the test vehicle if the body swings 
outside of the lane. This method has proved sufficient in determining 
if the vehicle remains in the lane. Moreover, agency testing on 
vehicles with a variety of overhangs indicates that a vehicle that is 
maintaining traction and control will not move laterally far enough for 
the rear of the vehicle to leave the traveled lane.
    Most importantly, the purpose of the braking-in-a-curve test is to 
represent a driving situation that might be encountered on a public 
road during a panic brake application. We believe that no part of the 
vehicle including a rear overhang should encroach on another travel 
lane. If the agency permitted the rear wheels of a vehicle to touch the 
outside of the 12-foot wide lane during the braking-in-a-curve test 
then the rear overhang would be outside of the travel lane and could 
pose a crash threat to other vehicles when that vehicle is operated on 
public roads.
    DaimlerChrysler also requested that NHTSA delete the requirement 
that the proposed braking-in-a-curve road surface be ``wet.'' The NPRM 
proposed that the braking-in-a-curve test be performed on a wet level 
surface having a peak friction coefficient (PFC) of 0.5. 
DaimlerChrysler indicated that the properties of test surface are 
adequately addressed by the command that it have a PFC equal to 0.5 
when measured by a specific procedure. In DaimlerChrysler's view, if 
the PFC is correct, the pavement could be dry or wet. We do not agree 
with DaimlerChrysler's position. The procedure used for measuring the 
PFC of the test surface--ASTM Method E1337-90--requires use of a wetted 
surface. If the surface must be wet to determine its coefficient of 
friction for testing, it must also be wet when testing occurs. NHTSA 
also believes that deleting the word ``wet'' from FMVSS No. 105 would 
lead to confusion, since it would not be clear if the vehicle test 
should be conducted with the test surface wetted or dry.
    Both NTEA and TMA voiced a number of objections to the agency 
proposal. As we observed above, NTEA urged the agency to terminate this 
rulemaking on the basis of its argument that no additional benefits are 
realized by adding the proposed test procedure to FMVSS No. 105 and 
FMVSS No. 121. Beyond that, NTEA objected to the additional costs and 
burdens imposed on final stage manufacturers by the proposal, arguing 
that pass-through certification will not be available and that their 
member companies do not have the means to conduct certification 
testing. NTEA contends that a final stage manufacturer can only be sure 
of compliance through actual testing. TMA raised similar objections to 
the costs imposed on final stage manufacturers by the proposal and 
argued that NHTSA has underestimated the costs and burdens that the 
regulations imposed on this segment of the industry. TMA also argued 
that adoption of the performance requirements for single unit vehicles 
would allow NHTSA to remove the existing equipment requirements for ABS 
from FMVSS No. 105 and FMVSS No. 121.
    It is NHTSA's position that adding performance requirements for 
single unit trucks is necessary and desirable. NHTSA does not claim 
that additional safety benefits above those projected in the agency's 
Final Economic Assessment (FEA) for the 1995 final rule establishing 
the ABS requirements will be attained solely from implementing a 
braking-in-a-curve test for single-unit vehicles.\4\ As detailed in 
that FEA, NHTSA estimated that the use of ABS on all heavy vehicles 
would help prevent between 320 and 506 fatalities, between 15,900 and 
27,413 injuries, and between $ 458 million and $ 553 million of 
property damage each year. These benefits assumed that ABS units 
installed on single-unit vehicles, which were not then subject to the 
braking-in-a-curve test, would be as effective as those installed on 
truck tractors. Therefore, now adding the braking-in-a-curve test for 
single unit vehicles does not modify those benefits.
---------------------------------------------------------------------------

    \4\ It should be noted that one commenter, Advocates, performed 
an analysis indicating that safety benefits would accrue for the 
establishment of ABS performance requirements for single-unit 
trucks.
---------------------------------------------------------------------------

    Adding this performance test is, in our view, necessary to ensure 
those previously calculated benefits are realized. NHTSA has 
encountered several instances in which ABS systems that met equipment 
requirements did not meet the braking-in-a-curve test. As we explained 
in the 1995 ABS final rule, the braking-in-a-curve test provides an 
important check of ABS performance. Merely requiring ABS systems to 
meet the ABS definition does not ensure that an ABS system will provide 
an acceptable level of performance.
    NHTSA does not agree with TMA's contention that the adoption of the 
braking-in-a-curve test for single unit vehicles eliminates the need 
for the ABS equipment requirements. As we discussed in the 1995 ABS 
final rule, we regard the braking-in-a-curve requirement as a 
complement to the ABS equipment requirement, and not as an alternative 
to it. (60 FR 13231) The braking-in-a-curve test alone can neither 
evaluate the overall effectiveness of ABS nor ensure the use of a 
closed-loop system. Such an evaluation would require an array of 
performance requirements such as split mu tests, surface transition 
tests, and stopping distance performance tests. However, the braking-
in-a-curve test is an objective, repeatable, and practicable procedure 
for evaluating the performance of a vehicle's ABS, and will be used by 
the agency to complement the ABS equipment requirement.
    The agency is not aware of, and TMA has not provided any data on, 
braking systems that provide stability and control during the braking-
in-a-curve test that do not use a closed-loop control strategy as 
required by the ABS equipment requirements. Thus, the agency has 
decided to retain the ABS equipment requirements in FMVSS Nos. 105 and 
121.
    We have also concluded that these requirements do not stifle 
innovation. Moreover, TMA did not provide specific examples of how the 
existing equipment requirements would prevent the use of new 
technologies. The agency is aware of new technologies such as the 
electronically-controlled braking system (ECBS) that has been developed 
by the industry, and is involved through the Society of Automotive 
Engineers in learning more about the characteristics, mechanical and 
electronic design features, and performance of ECBS. If appropriate, 
future rulemaking efforts can be undertaken to accommodate these 
systems in FMVSS No. 121. However, the agency sees no reason to 
consider deletion or modification of the ABS equipment requirements 
from FMVSS Nos. 105 and 121 until it has specific knowledge on how, or 
if, existing requirements impact on the use of alternate braking system 
technologies.
    TMA also stated that the proposed braking-in-a-curve test is not 
practicable. In TMA's view, NHTSA has not tested enough different axle 
combinations on single unit trucks to conclude that the proposed test 
is suitable for vehicles with different combinations of drive axles and 
``tag'' and ``pusher'' axles. NHTSA acknowledges that it has not 
performed the braking-in-a-curve test with more than the most common 
axle combinations. However, it is the agency's position that it need 
not do so.

[[Page 47491]]

Testing to date indicates that as long as wheel lock-up is prevented on 
at least the rearmost axle and the steer axle, the vehicle will remain 
stable during the braking-in-a-curve maneuver. None of the commenters, 
including TMA, submitted data to the agency indicating that NHTSA's 
testing on more conventional axle configurations is not applicable to 
other axle arrangements. Accordingly, NHTSA believes that the braking-
in-a-curve test is practicable for less common axle configurations.
    TMA and NTEA both objected to the burdens that adoption of the 
single unit braking-in-a-curve test would allegedly impose on final 
stage manufacturers. The agency's February 1995 FEA contained 
calculations of compliance costs for both the stopping distance and ABS 
requirements of the 1995 Final Rule. Using these costs as a starting 
point, the December 1999 NPRM contained an estimate for the cost of 
implementing the braking-in-a-curve test for single-unit trucks and 
buses. A stand-alone braking-in-a-curve test was estimated to cost 
$1500, and the incremental cost to incorporate the braking-in-a-curve 
test into a complete Standard No. 105 or 121 compliance test was set at 
$1,000. The cost per air-braked vehicle, when distributed across the 
affected population, was estimated to be about $18. In the later years, 
it was estimated that 30 compliance tests would be required annually, 
for a total cost of $360,000 (12 x 30 x $1,000). The cost per air-
braked vehicle in those later years would be about $6.
    In the case of hydraulic-braked single-unit vehicles, which were 
already subject to the existing test requirements of Standard No. 105, 
the 1995 FEA concluded that the incremental cost of a braking-in-a-
curve test would be $1,000 per test. The FEA estimated that 10 
manufacturers would have to complete 20 compliance tests each, the 
total cost for these vehicles would be approximately $200,000.00. Given 
annual sales of hydraulically braked medium and heavy trucks of 
approximately 195, 000 vehicles, we estimated the cost per vehicle for 
the braking-in-a-curve test for hydraulically braked vehicles at about 
$1. This cost per vehicle would be the same in the later years if 
manufacturers chose to test for each model year.
    TMA estimates that stand-alone braking-in-a-curve testing costs 
between $4,500 and $6,000 per test. TMA states that a typical burnish 
alone costs approximately $1,500 while a full FMVSS No. 105 or 121 
certification test costs $10,000 to $13,000. TMA did not provide a 
detailed breakdown of these costs, so it is difficult for NHTSA to 
ascertain how a braking-in-a-curve test, which is not 
disproportionately demanding in comparison to other tests in the 
sequence, could account for forty to fifty percent of the total cost of 
a complete FMVSS No. 105 or 121 certification test. TMA's comments also 
did not indicate what its members were currently expending in 
performing testing substantially similar to the test required by this 
final rule. Because, according to TMA's comments, TMA members are 
already using the SAE J1626 test procedure, TMA urged the agency to 
take steps to ensure that the FMVSS No. 121 and 105 braking-in-a-curve 
test conform as closely as possible to that test.
    A review of the SAEJ1626 test procedure indicates that it contains 
a braking-in-a-curve test that is virtually identical to the braking-
in-a-curve contained in this final rule. Therefore, it appears, to the 
extent that TMA members are already performing the SAE J1626 test, that 
the promulgation of this final rule should not impose additional test 
costs. If those manufacturers are not currently performing the SAE 
braking-in-a-curve test, the agency believes that TMA's claimed 
additional costs for adding the braking-in-a-curve test to FMVSS No. 
105 and 121 are overstated.
    Our own inquiries with test facilities indicate that adding the 
braking-in-a-curve test to the existing NHTSA test sequence should 
impose additional costs of approximately $1000, particularly since we 
are now specifying that the braking-in-a-curve test be performed only 
in the lightly loaded condition. In the agency's view, TMA's projected 
test costs of $4500 to $6000 for adding the braking in a curve test 
would be reasonable only in the situation where a vehicle has not been 
tested to SAE J1626, has already been tested to Standard No. 105 or 
121, and was being transported to a test facility only for testing to 
the braking-in-a-curve test with newly-installed and freshly burnished 
brakes.
    The NPRM indicated an estimated cost of $18 per air-braked single-
unit vehicle for manufacturers to include stand-alone braking-in-a-
curve testing in the first year and $6 in later years. In the case of 
hydraulically-braked vehicles, this figure is $1 per year for the first 
year and thereafter. As noted above, NHTSA does not agree that TMA's 
claimed costs are reasonable, particularly in light of the widespread 
use of the SAE J1626 test. However, if TMA's cost estimates were 
applied, then the per-vehicle cost could be as high as $54 to $72 per 
vehicle, provided the FEA and NPRM assumptions are valid on the number 
of tests to be conducted. However, as indicated above, NHTSA believes 
that testing costs as high as those projected by TMA represent an 
unlikely worst case and that the agency's projection are much more 
representative of actual conditions. We also note that the cost of ABS 
components and complete systems has declined approximately 30 percent 
in the 7 years since the cost-benefit analysis contained in the FEA was 
performed, thereby reducing the overall cost of compliance.
    NTEA also commented on the costs of the agency proposal. The 
organization contends that the costs of complying with the braking-in-
a-curve requirement would be particularly burdensome for its members. 
NTEA describes these members as small businesses that sell and install 
truck bodies on incomplete vehicles. Some of these vehicles are 
obtained from incomplete vehicle manufacturers in a nearly complete 
condition such as a chassis-cab, i.e., a truck that is complete except 
for a body. In the case of a chassis-cab, the final stage manufacturer 
typically adds a body to the portion of the vehicle behind the cab to 
produce a completed truck. Other configurations, such as cutaways, 
stripped chassis or chassis cowls require substantially more work 
before the vehicle is complete. NTEA believes that as much as 20 
percent of all single unit trucks built in multiple stages are based on 
cutaways, stripped chassis or chassis cowls. According to the 
organization, when these types of incomplete vehicles are used, the 
final stage manufacturer can only certify the completed vehicle through 
testing. NTEA also stated that even where a chassis cab or other 
incomplete vehicle that has been certified by the incomplete vehicle 
manufacturer, the particular application for the vehicle may require 
sufficient changes so the final stage vehicle no longer complies with 
the specifications contained in the incomplete vehicle manufacturer's 
certification. In both cases, NTEA commented that the final stage 
manufacturer would then face the practical and financial obstacles of 
obtaining and paying for the required compliance tests.
    NHTSA agrees that final stage manufacturers may not be able to rely 
on a certification provided by an incomplete vehicle manufacturer or 
that such a certification may not exist. However, it is our view that 
NTEA's claims are overstated, and like those presented by the TMA, 
present a worst-case scenario as the norm. We note first that chassis-
cabs, for which pass through certification is available,

[[Page 47492]]

represent a significant portion of the affected population. For 
instance, in the 1987 through 1989 model years, chassis-cabs 
represented 86 percent of sales of incomplete trucks with a GVWR above 
10,000 pounds. Based on inquiries with manufacturers, NHTSA believes 
that this percentage is now much larger. Finally, even where pass-
through certification is not available, incomplete vehicle 
manufacturers provide certification data for specific Federal motor 
vehicle safety standards that can be used by the final stage 
manufacturer to certify compliance without having to do any testing. 
Examination of this documentation shows that final stage manufacturers 
are usually provided with an envelope within which the vehicle center-
of-gravity can be located and the axle loadings that can be used in 
order for the vehicle to meet either Standard No. 105 or Standard No. 
121. Incomplete vehicle manufacturers strive to make this information 
as complete as possible in order to serve their customers. Therefore, 
NHTSA believes that occurrences where final stage manufacturers may not 
rely on pass-through certification or vehicle certification data from 
the incomplete vehicle manufacturer will be rare and would represent a 
significantly smaller percentage of the affected vehicles than the 20 
percent claimed by NTEA.
    NTEA also argues that the tremendous variety of vehicle 
configurations produced by its members compels the conclusion that 
NHTSA cannot require these member companies to perform the braking-in-
a-curve test. This argument is based on two assertions. The first is 
that its members who do not use chassis-cabs and do not have pass-
through certification have no choice but to perform compliance testing 
to demonstrate compliance with FMVSS Nos. 105 and 121. The second is 
that for those manufacturers, the costs of testing are so great as to 
make it impracticable. As testing must be both objective and 
practicable and NTEA's members have no choice but to test, the costs of 
the braking-in-a-curve test, in NTEA's view, preclude use of the test.
    The NTEA position relies heavily on the decisions in two prior 
challenges the agency final rules, Paccar, Inc. v. National Highway 
Traffic Safety Administration, 573 F.2d 632 (9th Cir.), cert. denied, 
439 U.S. 862, 99 S. Ct. 184, 58 L. Ed. 2d 172 (1978) and NTEA v. 
National Highway Traffic Safety Administration, 919 F.2d 1148, 1152-53 
(6th Cir. 1990) where the courts rejected the agency's argument that 
compliance could be demonstrated by a showing of due care when tests 
are not performed. In both cases, NHTSA had conceded that the required 
tests were impracticable. This left the courts to consider the question 
of whether the due care standard provided sufficient guidance to 
manufacturers when no compliance test was available. The Paccar court, 
describing the due care standard as ``amorphous,'' found that NHTSA's 
``suggestions'' of what constituted due care to be too imprecise to 
assist those trying to meet the standard at issue. In the NTEA case, 
the court followed the earlier Paccar decision and held that NHTSA 
could not impose a due care requirement on final stage manufacturers 
for whom the designated test was impracticable. NTEA argues that 
imposing the braking-in-a-curve test to final stage manufacturers is 
equally impracticable as the tests involved in both the Paccar and NTEA 
decisions. As the agency has not proposed any alternative to the test 
other than to establish compliance through due care, NTEA contends that 
NHTSA cannot now apply the braking-in-a-curve test to final stage 
manufacturers.
    NHTSA does not agree with NTEA's analysis. We note first that NTEA 
did not provide any data supporting its position that the braking-in-a-
curve test is so costly as to be impracticable. In fact, NTEA's 
comments do not contain any cost estimates for this test. In the 
absence of any cost estimates, NTEA stresses that the tremendous 
variety of vehicles made by final stage manufacturers who cannot rely 
on pass-through certification supports the premise that the braking-in-
a-curve test is impracticable. According to NTEA, requiring final stage 
manufacturers to perform the braking-in-a-curve test is tantamount to 
requiring that every vehicle produced by these manufacturers must 
undergo this test. However, as is the case with cost estimates for the 
test itself, NTEA does not provide any data on the production of final 
stage manufacturers, including how many manufacturers produce models in 
extremely low volumes. In some instances, final stage manufacturers 
will be able to spread the cost of testing over the production run of 
similar vehicles. In other instances, manufacturers may have to perform 
testing of a single vehicle. Unlike the tests involved in both the 
Paccar and NTEA cases, the braking-in-a-curve test simply adds a new 
component to a braking test sequence that manufacturers are already 
required to perform. This incremental addition to the existing test 
sequence does not, in contrast to the test in the NTEA case, damage the 
test vehicle.
    We estimate that the incremental cost of performing the braking-in-
a-curve test to be approximately $1000.00. Manufacturers, even final 
stage manufacturers producing specialized vehicles on a bare chassis, 
rarely produce just one example of a particular design. The incremental 
cost of the braking-in-a-curve test is therefore likely to be spread 
over a production run of many vehicles. Even in the case of a 
production run of just one vehicle, we do not believe that this 
additional test cost is so high as to make the braking-in-a-curve test 
impractible, particularly since a buyer seeking a highly specialized 
vehicle is likely to be willing to pay more for the special features it 
offers.
    NHTSA also believes that final stage manufacturers are capable of 
determining what constitutes the exercise of due care when certifying a 
vehicle and may rely on the exercise of that care in establishing 
certification without testing. While we must concede that NHTSA cannot 
make a single pronouncement of what constitutes due care for every 
circumstance in which a manufacturer certifies a vehicle, 
manufacturers, even final stage manufacturers, should be able to make 
this determination themselves. Vehicle manufacturers, both large and 
small, must make similar determinations for liability purposes every 
day. In so doing, they are aided by the application of industry and 
professional standards of care.
    Final stage manufacturers are also provided with considerable 
guidance by the incomplete vehicle documents and body builder's guides 
provided by chassis manufacturers. Even where pass-through 
certification cannot be used, incomplete vehicle documents provide 
assurance of compliance if the completed vehicle meets the axle loading 
and center-of-gravity specifications provided by the incomplete vehicle 
manufacturer. If the final stage manufacturer stays within the 
guidelines provided by the incomplete vehicle manufacturer, the 
certification information supplied with the chassis can be used to 
certify compliance without doing any actual testing. Moreover, each 
chassis-cab manufacturer has an incentive to make the requirements for 
pass-through certification as broad as possible. The final stage 
manufacturer can then select from a variety of readily-available 
chassis-cab configurations and options (e.g., wheelbase, front and rear 
axle ratings) that can predictably meet the pass-through certification 
criteria.
    When a final stage manufacturer completes a vehicle in a way that 
takes

[[Page 47493]]

the vehicle outside the specifications of the IVD, then it cannot rely 
on the IVD in certifying compliance of the vehicle. Absent actual 
testing, alternate means of certification, such as engineering analysis 
or computer simulation, may be sufficient to allow a final stage 
manufacturer to certify compliance in good faith. For example, the 
manufacturer or supplier of the lift axle, upon request from a final 
stage manufacturer, may provide service brake retardation force 
characteristics for the axles it sells, based on dynamometer or other 
testing conducted by the axle manufacturer, which can be applied 
through simple calculations to determine compliance with service brake 
stopping distance requirements. That supplier can also provide grade-
holding or drawbar test data to determine, using simple calculations, 
that the parking brake requirements in FMVSS No. 121, for example, are 
met at the increased GVWR as altered by the final stage manufacturer. 
Other braking requirements in the FMVSSs, including emergency brake 
stopping distance and brake actuation and release timing, can similarly 
be met by performing engineering analysis, working with chassis 
manufacturers and brake system and axle suppliers, and installing 
suitable equipment, to permit the final stage manufacturer to certify 
compliance with FMVSS Nos. 105 or 121. In many cases, such 
certification can be achieved without having to conduct actual road 
testing, or in some cases, with only portions of road or laboratory 
testing required (such as hiring a consultant to perform brake 
application and release timing tests at the final stage manufacturer's 
facilities).
    NHTSA recognizes that there may be unusual vehicle configurations 
for which complete data are not available from vehicle or component 
suppliers that would enable an engineering analysis to be used for 
certification purposes. In such cases, computer simulations or actual 
road testing may be necessary for certification. Final stage 
manufacturers should consider these facts before deciding to build 
unusual vehicle configurations, since it is predictable that some 
vehicles cannot be certified using engineering analyses prior to 
purchasing a chassis, body, or other equipment.

VI. Preselection of Test Condition Option

    Many FMVSSs contain alternative compliance options from which 
vehicle manufacturers may choose. In this final rule, there is an 
option to use a rollbar structure of up to 1,000 pounds for vehicles 
tested in the lightly-loaded condition. This has resulted in some 
problems when the agency conducts its compliance tests. For example, in 
a recent case, a vehicle was tested to FMVSS No. 135 and did not meet 
one of the requirements of that standard. When contacted about the non-
compliance, the vehicle manufacturer stated that the vehicle should be 
compliance tested to FMVSS No. 105, since at that time that particular 
vehicle could be manufactured to either standard at the vehicle 
manufacturer's option. Thus, the agency was faced with having to test 
to two standards to determine which one applied.
    To avoid confusion in the future, the agency is now conducting a 
review of compliance test condition options and anticipates that it 
will propose regulations to address this issue. However, until such 
rules are proposed and adopted, our practice will be to address 
optional test conditions in each standard. Thus, the agency is adding a 
statement to the general test conditions for both FMVSS No. 105 (S6.15) 
and 121 (S6.1.16) that directs a vehicle manufacturer to identify which 
option was selected for compliance test purposes. The agency does not 
believe that this makes any of the standard's requirements more 
stringent. Instead, it removes uncertainty from the compliance test 
program and reduces test costs to the agency.

VII. Effective Date

    The amendments contained in this final rule become effective 
October 10, 2003. With the exception of vehicles built in two or more 
stages, the braking-in-a-curve test requirements contained in this 
final rule apply to vehicles built on or after July 1, 2005. Vehicles 
built in two or more stages must meet the braking-in-a-curve test's 
requirements on or after July 1, 2006. Single unit trucks and buses are 
built in a wide variety of configurations to meet a diverse array of 
uses and needs. Many single unit trucks and buses are built to standard 
designs and configurations. However, many are specialty vehicles 
dedicated to specific purposes. Although anti-lock brake systems 
suitable for use in these vehicles are readily available, adaptation of 
these systems for particular applications will require sufficient 
leadtime to allow whatever development and testing may be needed. 
Moreover, as many single unit trucks and buses are manufactured in two 
or more stages, the agency notes that many final stage manufacturers 
are likely to rely on incomplete vehicle manufacturers to supply 
chassis that meet the new requirements. The agency has determined that 
the approximately two-year leadtime provided in this final rule 
provides sufficient time for intermediate stage manufacturers to 
develop complying incomplete vehicles in a sufficient number of 
configurations to meet the needs of final stage manufacturers. Finally, 
this final rule will make it necessary for some small final stage 
manufacturers to certify their vehicles with limited assistance from 
the intermediate vehicle manufacturer. The compliance date chosen by 
the agency affords these manufacturers sufficient time to take whatever 
steps may be required to meet the new requirements. Accordingly, the 
agency finds that good cause exists to make the compliance dates in 
this final rule effective more than one year after issuance.

VIII. Rulemaking Analyses and Notices

A. Regulatory Policies and Procedures

    Executive Order 12866, ``Regulatory Planning and Review,'' (58 FR 
51735, October 4, 1993), provides for making determinations whether a 
regulatory action is ``significant'' and therefore subject to Office of 
Management and Budget (OMB) review and to the requirements of the 
Executive Order. The Order defines a ``significant regulatory action'' 
as one that is likely to result in a rule that may:
    (1) Have an annual effect on the economy of $100 million or more or 
adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety, or State, local, or Tribal governments or 
communities;
    (2) Create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    (3) Materially alter the budgetary impact of entitlements, grants, 
user fees, or loan programs or the rights and obligations of recipients 
thereof; or
    (4) Raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order.
    We have considered the impact of this rulemaking action under 
Executive Order 12866 and the Department of Transportation's regulatory 
policies and procedures. The Office of Management and Budget did not 
review this rulemaking document under E.O. 12866. The document is also 
not considered to be significant under the Department's Regulatory 
Policies and Procedures (44 FR 11034; February 26, 1979).
    This document amends 49 CFR Parts 571.105 and 571.121 by extending 
the application of the existing braking-in-a-curve performance test for 
anti-lock

[[Page 47494]]

brakes to vehicles already required to be equipped with such brakes. By 
providing a compliance test, this final rule assures the realization of 
the benefits previously calculated when the requirement for 
installation of anti-lock brakes was issued in 1995. The compliance 
test contained in this final rule, which requires a vehicle to 
successfully negotiate a curved lane on a wetted low-friction surface, 
is identical to the existing agency test applicable to truck tractors, 
virtually identical to an existing Society of Automotive Engineers 
(SAE) test, and similar to other industry tests used to evaluate anti-
lock brakes. Therefore, NHTSA believes that existing ABS systems, when 
properly installed and configured, will allow a vehicle to meet the 
requirements of the braking-in-a-curve test.
    By extending the braking-in-a-curve test to non-articulated trucks 
and buses, this final rule adds a new road test requirement to an 
existing sequence of road tests for those vehicles. The costs of the 
new additional road test required by this final rule are (because the 
tests are identical) identical to the costs of requiring truck tractors 
to meet the same test. Based on our knowledge of this braking-in-a-
curve test, the agency estimated the incremental cost of adding this 
new road test to the existing sequence of road tests for brakes to be 
approximately $1,000 per test. In most cases, this additional test cost 
will be spread over hundreds or thousands of vehicles. In instances in 
which the vehicle involved is a more specialized configuration, the 
cost of compliance testing, including the cost of including the 
braking-in-a-curve test in the existing road test sequence will be 
spread over fewer vehicles. Overall, NHTSA estimates that approximately 
250,000 single unit trucks and 7,000 single-unit buses will be affected 
by this final rule. Testing costs were estimated at the time of the 
1995 final rule to range from $1 to $18 per vehicle, depending on 
whether the vehicle has air brakes or hydraulic brakes and if the 
braking-in-a-curve test is as part of a full brake system compliance 
test or is performed alone.
    When we promulgated the anti-lock brake requirements in 1995, the 
benefits of the anti-lock brake requirements were estimated to result 
in as many as 506 fewer annual fatalities, 27,413 fewer injuries and a 
reduction of property damage by as much as $553 million each year. The 
increased cost, which included the cost of anti-lock brakes and testing 
combined, was estimated to be $692 per vehicle. Almost all of that cost 
is for the brakes themselves. The cost of the brakes is attributable to 
the March 1995 final rule, not this one.

B. Executive Order 13132 (Federalism)

    The agency has analyzed this rulemaking action in accordance with 
the principles and criteria set forth in Executive Order 13132. This 
final rule does not have substantial direct effects on the States, on 
the relationship between the national government and the States, or on 
the distribution of power and responsibilities among the various levels 
of government, as specified in Executive Order 13132. Accordingly, the 
requirements of section 6 of the Executive Order do not apply to this 
final rule.

C. Executive Order 13045

    Executive Order 13045 (62 FR 19885, April 23, 1997) applies to any 
rule that: (1) is determined to be ``economically significant'' as 
defined under E.O. 12866, and (2) concerns an environmental, health or 
safety risk that NHTSA has reason to believe may have a 
disproportionate effect on children. If the regulatory action meets 
both criteria, we must evaluate the environmental health or safety 
effects of the planned rule on children, and explain why the planned 
regulation is preferable to other potentially effective and reasonably 
feasible alternatives considered by us.
    This rule is not subject to the Executive Order because it is not 
economically significant as defined in E.O. 12866 and does not involve 
decisions based on environmental, safety or health risks having a 
disproportionate impact on children.

D. Executive Order 12778

    Pursuant to Executive Order 12778, ``Civil Justice Reform,'' we 
have considered whether this final rule will have any retroactive 
effect. We conclude that it will not have such effect.
    Under 49 U.S.C. 30103, whenever a Federal motor vehicle safety 
standard is in effect, a State may not adopt or maintain a safety 
standard applicable to the same aspect of performance which is not 
identical to the Federal standard, except to the extent that the state 
requirement imposes a higher level of performance and applies only to 
vehicles procured for the State's use. 49 U.S.C. 30161 sets forth a 
procedure for judicial review of final rules establishing, amending or 
revoking Federal motor vehicle safety standards. That section does not 
require submission of a petition for reconsideration or other 
administrative proceedings before parties may file suit in court.

E. Regulatory Flexibility Act

    Pursuant to the Regulatory Flexibility Act (5 U.S.C. 601 et seq., 
as amended by the Small Business Regulatory Enforcement Fairness Act 
(SBREFA) of 1996) whenever an agency is required to publish a notice of 
rulemaking for any proposed or final rule, it must prepare and make 
available for public comment a regulatory flexibility analysis that 
describes the effect of the rule on small entities (i.e., small 
businesses, small organizations, and small governmental jurisdictions). 
However, no regulatory flexibility analysis is required if the head of 
an agency certifies the rule will not have a significant economic 
impact on a substantial number of small entities. SBREFA amended the 
Regulatory Flexibility Act to require Federal agencies to provide a 
statement of the factual basis for certifying that a rule will not have 
a significant economic impact on a substantial number of small 
entities.
    The Administrator has considered the effects of this rulemaking 
action under the Regulatory Flexibility Act (5 U.S.C. Sec.  601 et 
seq.) and certifies that this final rule will not have a significant 
economic impact on a substantial number of small entities.
    This final rule extends application of an existing performance test 
for anti-lock brakes to a class of vehicles that are already required 
to have anti-lock brakes. The performance test, known as the braking-
in-a-curve test, previously applied only to truck tractors and this 
final rule simply requires that single unit (non-articulated) trucks 
and buses must meet the same test. The primary cost effect of the 
requirements will be testing costs and will be on manufacturers of 
single unit (i.e., non-articulated) trucks and buses. Some single unit 
trucks and buses are produced by large manufacturers. Other single unit 
trucks and buses are produced in stages. In most cases, large 
manufacturers provide incomplete vehicles to smaller final stage 
manufacturers, who then produce the finished vehicle. Final stage 
manufacturers, those who use incomplete vehicles produced by larger 
manufacturers to produce specialty products, are generally small 
businesses. However, NHTSA believes that this final rule is not 
burdensome for final stage manufacturers. As eighty to ninety percent 
of the affected vehicles are completed from chassis-cabs where pass 
through certification is available, most final stage manufacturers will 
be able to rely on the prior certification and testing performed by an 
incomplete vehicle manufacturer and thus will not

[[Page 47495]]

need to incur additional costs. The remaining final stage manufacturers 
will be required to perform testing or take other steps to ensure that 
the vehicles they produce will meet the new performance requirements. 
These manufacturers will have a variety of means available to 
accomplish this, including access to test and other data performed by 
chassis manufacturers, trade groups and equipment manufacturers. 
Therefore, the agency has determined that this final rule will not have 
a significant impact on these small entities and has not prepared a 
regulatory flexibility analysis.

F. National Environmental Policy Act

    We have analyzed this final rule amendment for the purposes of the 
National Environmental Policy Act and determined that it will not have 
any significant impact on the quality of the human environment.

G. Paperwork Reduction Act

    Under the Paperwork Reduction Act of 1995, a person is not required 
to respond to a collection of information by a Federal agency unless 
the collection displays a valid OMB control number. This final rule 
does not contain any new information collection requirements.

H. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (NTTAA), Public Law 104-113, section 12(d) (15 U.S.C. 272) 
directs us to use voluntary consensus standards in its regulatory 
activities unless doing so would be inconsistent with applicable law or 
otherwise impractical. Voluntary consensus standards are technical 
standards (e.g., materials specifications, test methods, sampling 
procedures, and business practices) that are developed or adopted by 
voluntary consensus standards bodies. The NTTAA directs us to provide 
Congress, through OMB, explanations when we decide not to use available 
and applicable voluntary consensus standards.
    This final rule adds anti-lock brake system performance 
requirements and a performance test for single unit trucks to 49 CFR 
571.105 and 49 CFR 571.121. The amendments add these new requirements 
to an existing regulatory scheme that already contains an identical 
test for truck tractors. The tests adopted in this final rule are 
identical in most respects to the provisions of Section 5.3 of the 
Society of Automotive Engineers (SAE) Recommended Practice J1626, 
Braking, Stability, and Control Performance Test Procedures for Air and 
Hydraulic Brake Equipped Trucks. Any differences between the provisions 
of this final rule and SAE J1626 are minor in nature and do not add 
significantly to the test burdens of manufacturers. Accordingly, to the 
degree that the final rule does not adopt a voluntary consensus 
standard, the agency believes that no explanation is necessary.

I. Unfunded Mandates Reform Act

    Section 202 of the Unfunded Mandates Reform Act of 1995 (UMRA) 
requires Federal agencies to prepare a written assessment of the costs, 
benefits and other effects of proposed or final rules that include a 
Federal mandate likely to result in the expenditure by State, local or 
tribal governments, in the aggregate, or by the private sector, of more 
than $100 million in any one year (adjusted for inflation with base 
year of 1995). Before promulgating a NHTSA rule for which a written 
statement is needed, section 205 of the UMRA generally requires us to 
identify and consider a reasonable number of regulatory alternatives 
and adopt the least costly, most cost-effective or least burdensome 
alternative that achieves the objectives of the rule.
    The provisions of section 205 do not apply when they are 
inconsistent with applicable law. Moreover, section 205 allows us to 
adopt an alternative other than the least costly, most cost-effective 
or least burdensome alternative if we publish with the final rule an 
explanation why that alternative was not adopted.
    This final rule will not result in costs of $100 million or more to 
either State, local, or tribal governments, in the aggregate, or to the 
private sector. Thus, this final rule is not subject to the 
requirements of sections 202 and 205 of the UMRA.

J. Regulation Identifier Number (RIN)

    The Department of Transportation assigns a regulation identifier 
number (RIN) to each regulatory action listed in the Unified Agenda of 
Federal Regulations. The Regulatory Information Service Center 
publishes the Unified Agenda in April and October of each year. You may 
use the RIN contained in the heading at the beginning of this document 
to find this action in the Unified Agenda.

List of Subjects in 49 CFR Part 571

    Imports, Motor vehicle safety, Motor vehicles, Rubber and rubber 
products, Tires.

0
In consideration of the foregoing, 49 CFR part 571 is amended as 
follows:

PART 571--[AMENDED]

0
1. The authority citation for part 571 continues to read as follows:

    Authority: 49 U.S.C. 322, 21411, 21415, 21417, and 21466; 
delegation of authority at 49 CFR 1.50.


0
2. Section 571.105 is amended by revising S4 to add definitions of 
``Full brake application'' and ``Maximum drive-through speed;'' by 
revising S5.1, S6.1.1, S6.1.2, S6.9.2, the introductory text of S7, 
S7.5, and Table 1; and by adding S5.1.7, S6.14 and S6.15, to read as 
follows:


Sec.  571.105  Standard No. 105, Hydraulic brake systems.

* * * * *
    S4 Definitions.
* * * * *
    Full brake application means a brake application in which the force 
on the brake pedal reaches 150 pounds within 0.3 seconds from the point 
of application of force to the brake control.
* * * * *
    Maximum drive-through speed means the highest possible constant 
speed at which the vehicle can be driven through 200 feet of a 500-foot 
radius curve arc without leaving the 12-foot lane.
* * * * *
    S5.1 Service brake systems. Each vehicle must be equipped with a 
service brake system acting on all wheels. Wear of the service brake 
must be compensated for by means of a system of automatic adjustment. 
Each passenger car and each multipurpose passenger vehicle, truck, and 
bus with a GVWR of 10,000 pounds or less must be capable of meeting the 
requirements of S5.1.1 through S5.1.6 under the conditions prescribed 
in S6, when tested according to the procedures and in the sequence set 
forth in S7. Each school bus with a GVWR greater than 10,000 pounds 
must be capable of meeting the requirements of S5.1.1 through S5.1.5, 
and S5.1.7 under the conditions specified in S6, when tested according 
to the procedures and in the sequence set forth in S7. Each 
multipurpose passenger vehicle, truck and bus (other than a school bus) 
with a GVWR greater than 10,000 pounds must be capable of meeting the 
requirements of S5.1.1, S5.1.2, S5.1.3, and S5.1.7 under the conditions 
specified in S6, when tested according to the procedures and in the 
sequence set forth in S7. Except as noted in S5.1.1.2 and S5.1.1.4, if 
a vehicle is incapable of attaining a speed specified in S5.1.1, 
S5.1.2, S5.1.3, or S5.1.6, its service brakes must be capable of 
stopping the vehicle from the multiple of 5 mph that is 4 to 8 mph less 
than

[[Page 47496]]

the speed attainable in 2 miles, within distances that do not exceed 
the corresponding distances specified in Table II. If a vehicle is 
incapable of attaining a speed specified in S5.1.4 in the time or 
distance interval set forth, it must be tested at the highest speed 
attainable in the time or distance interval specified.
* * * * *
    S5.1.7 Stability and control during braking. When stopped four 
consecutive times under the conditions specified in S6, each vehicle 
with a GVWR greater than 10,000 pounds manufactured on or after July 1, 
2005 and each vehicle with a GVWR greater than 10,000 pounds 
manufactured in two or more stages on or after July 1, 2006 shall stop 
from 30 mph or 75 percent of the maximum drive-through speed, whichever 
is less, at least three times within the 12-foot lane, without any part 
of the vehicle leaving the roadway. Stop the vehicle with the vehicle 
at its lightly loaded vehicle weight, or at the manufacturer's option, 
at its lightly loaded vehicle weight plus not more than an additional 
1000 pounds for a roll bar structure on the vehicle.
* * * * *
    S6.1.1 Other than tests specified at lightly loaded vehicle weight 
in S7.5(a), S7.7, S7.8, and S7.9, the vehicle is loaded to its GVWR 
such that the weight on each axle as measured at the tire-ground 
interface is in proportion to its GAWR, except that each fuel tank is 
filled to any level from 100 percent of capacity (corresponding to full 
GVWR) to 75 percent. However, if the weight on any axle of a vehicle at 
lightly loaded vehicle weight exceeds the axle's proportional share of 
the gross vehicle weight rating, the load required to reach GVWR is 
placed so that the weight on that axle remains the same as a lightly 
loaded vehicle weight.
* * * * *
    S6.1.2 For the applicable tests specified in S7.5(a), S7.7, S7.8, 
and S7.9, vehicle weight is lightly loaded vehicle weight, with the 
added weight distributed in the front passenger seat area in passenger 
cars, multipurpose passenger vehicles, and trucks, and in the area 
adjacent to the driver's seat in buses.
* * * * *
    S6.9.2(a) For vehicles with a GVWR greater than 10,000 pounds, road 
tests (excluding stability and control during braking tests) are 
conducted on a 12-foot-wide, level roadway, having a peak friction 
coefficient of 0.9 when measured using an American Society for Testing 
and Materials (ASTM) E 1136 standard reference test tire, in accordance 
with ASTM Method E 1337-90, at a speed of 40 mph, without water 
delivery. Burnish stops are conducted on any surface. The parking brake 
test surface is clean, dry, smooth, Portland cement concrete.
    S6.9.2(b) For vehicles with a GVWR greater than 10,000 pounds, 
stability and control during braking tests are conducted on a 500-foot-
radius curved roadway with a wet level surface having a peak friction 
coefficient of 0.5 when measured on a straight or curved section of the 
curved roadway using an American Society for Testing and Materials 
(ASTM) E1136 standard reference tire, in accordance with ASTM Method 
E1337-90, at a speed of 40 mph, with water delivery.
* * * * *
    S6.14 Special drive conditions. A vehicle with a GVWR greater than 
10,000 pounds equipped with an interlocking axle system or a front 
wheel drive system that is engaged and disengaged by the driver is 
tested with the system disengaged.
    S6.15 Selection of compliance options. Where manufacturer options 
are specified, the manufacturer shall select the option by the time it 
certifies the vehicle and may not thereafter select a different option 
for the vehicle. Each manufacturer shall, upon request from the 
National Highway Traffic Safety Administration, provide information 
regarding which of the compliance options it has selected for a 
particular vehicle or make/model.
* * * * *
    S7. Test procedure and sequence. Each vehicle shall be capable of 
meeting all the applicable requirements of S5 when tested according to 
the procedures and sequence set forth below, without replacing any 
brake system part or making any adjustments to the brake system other 
than as permitted in the burnish and reburnish procedures and in S7.9 
and S7.10. (For vehicles only having to meet the requirements of 
S5.1.1, S5.1.2, S5.1.3, and S5.1.7 in section S5.1, the applicable test 
procedures and sequence are S7.1, S7.2, S7.4, S7.5(b), S7.5(a), S7.8, 
S7.9, S7.10, and S7.18. However, at the option of the manufacturer, the 
following test procedure and sequence may be conducted: S7.1, S7.2, 
S7.3, S7.4, S7.5(b), S7.6, S7.7, S7.5(a), S7.8, S7.9, S7.10, and S7.18. 
The choice of this option must not be construed as adding to the 
requirements specified in S5.1.2 and S5.1.3.) Automatic adjusters must 
remain activated at all times. A vehicle shall be deemed to comply with 
the stopping distance requirements of S5.1 if at least one of the stops 
at each speed and load specified in each of S7.3, S7.5(b), S7.8, S7.9, 
S7.10, S7.15 and S7.17 (check stops) is made within a stopping distance 
that does not exceed the corresponding distance specified in Table II. 
When the transmission selector control is required to be in neutral for 
a deceleration, a stop or snub must be obtained by the following 
procedures:
    (a) Exceed the test speed by 4 to 8 mph;
    (b) Close the throttle and coast in gear to approximately 2 mph 
above the test speed;
    (c) Shift to neutral; and
    (d) When the test speed is reached, apply the service brakes.
* * * * *
    S7.5 (a) Stability and control during braking (vehicles with a GVWR 
greater than 10,000 pounds). Make four stops in the lightly-loaded 
weight condition specified in S5.1.7. Use a full brake application for 
the duration of the stop, with the clutch pedal depressed or the 
transmission selector control in the neutral position, for the duration 
of each stop.
    (b) Service brake system--second effectiveness test. For vehicles 
with a GVWR of 10,000 pounds or less, or any school bus, make six stops 
from 30 mph. Then, for any vehicle, make six stops from 60 mph. Then, 
for a vehicle with a GVWR of 10,000 pounds or less, make four stops 
from 80 mph if the speed attainable in 2 miles is not less than 84 mph.
* * * * *

                            Table I.--Brake Test Procedure Sequence and Requirements
----------------------------------------------------------------------------------------------------------------
                                               Test load
             Sequence             ----------------------------------     Test procedure          Requirements
                                        Light             GVWR
----------------------------------------------------------------------------------------------------------------
1. Instrumentation check.........  ...............  ...............  S7.2                    ...................
2. First (preburnish)              ...............               X   S7.3..................  S5.1.1.1
 effectiveness test.
3. Burnish procedure.............  ...............               X   S7.4                    ...................

[[Page 47497]]

 
4. Second effectiveness test.....  ...............               X   S7.5(b)...............  S5.1.1.2
5. First reburnish...............  ...............               X   S7.6..................  ...................
6. Parking brake.................               X                X   S7.7..................  S5.2
7. Stability and control during                 X   ...............  S7.5(a)...............  S5.1.7
 braking (braking-in-a-curve
 test).
8. Third effectiveness (lightly                 X   ...............  S7.8..................  S5.1.1.3
 loaded vehicle).
9. Partial failure...............               X                X   S7.9..................  S5.1.2
10. Inoperative brake power and    ...............               X   S7.10.................  S5.1.3
 power assist units.
11. First fade and recovery......  ...............               X   S7.11.................  S5.1.4
12. Second reburnish.............  ...............               X   S7.12                   ...................
13. Second fade and recovery.....  ...............               X   S7.13.................  S5.1.4
14. Third reburnish..............  ...............               X   S7.14                   ...................
15. Fourth effectiveness.........  ...............               X   S7.15.................  S5.1.1.4
16. Water recovery...............  ...............               X   S7.16.................  S5.1.5
17. Spike stops..................  ...............               X   S7.17.................  S5.1.6
18. Final inspection.............  ...............  ...............  S7.18.................  S5.6
19. Moving barrier test..........  ...............               X   S7.19.................  S5.2.2.3
----------------------------------------------------------------------------------------------------------------

* * * * *

0
3. Section 571.121 is amended by revising S5.3, S5.3.6, S5.3.6.2 and 
Table 1; and by adding S6.1.17, to read as follows:


Sec.  571.121  Air brake systems

* * * * *
    S5.3 Service brakes--road tests. The service brake system on each 
truck tractor shall, under the conditions of S6, meet the requirements 
of S5.3.1, S5.3.3, S5.3.4, and S5.3.6, when tested without adjustments 
other than those specified in this standard. The service brake system 
on each bus and truck (other than a truck tractor shall) manufactured 
before July 1, 2005 and each bus and truck (other than a truck tractor) 
manufactured in two or more stages shall, under the conditions of S6, 
meet the requirements of S5.3.1, S5.3.3, and S5.3.4 when tested without 
adjustments other than those specified in this standard. The service 
brake system on each bus and truck (other than a truck tractor) 
manufactured on or after July 1, 2005 and each bus and truck (other 
than a truck tractor) manufactured in two or more stages on or after 
July 1, 2006 shall, under the conditions of S6, meet the requirements 
of S5.3.1, S5.3.3, S5.3.4, and S5.3.6, when tested without adjustments 
other than those specified in this standard. The service brake system 
on each trailer shall, under the conditions of S6, meet the 
requirements of S5.3.3, S5.3.4, and S5.3.5 when tested without 
adjustments other than those specified in this standard. However, a 
heavy hauler trailer and the truck and trailer portions of an auto 
transporter need not met the requirements of S5.3.
* * * * *
    S5.3.6 Stability and control during braking--trucks and buses. When 
stopped four consecutive times for each combination of weight, speed, 
and road conditions specified in S5.3.6.1 and S5.3.6.2, each truck 
tractor shall stop at least three times within the 12-foot lane, 
without any part of the vehicle leaving the roadway. When stopped four 
consecutive times for each combination of weight, speed, and road 
conditions specified in S5.3.6.1 and S5.3.6.2, each bus and truck 
(other than a truck tractor) manufactured on or after July 1, 2005, and 
each bus and truck (other than a truck tractor) manufactured in two or 
more stages on or after July 1, 2006, shall stop at least three times 
within the 12-foot lane, without any part of the vehicle leaving the 
roadway.
* * * * *
    S5.3.6.2 Stop the vehicle, with the vehicle:
    (a) Loaded to its GVWR, for a truck tractor, and
    (b) At its unloaded weight plus up to 500 pounds (including driver 
and instrumentation), or at the manufacturer's option, at its unloaded 
weight plus up to 500 pounds (including driver and instrumentation) and 
plus not more than an additional 1000 pounds for a roll bar structure 
on the vehicle, for a truck, bus, or truck tractor.
* * * * *
    S6.1.17 Selection of compliance options. Where manufacturer options 
are specified, the manufacturer shall select the option by the time it 
certifies the vehicle and may not thereafter select a different option 
for the vehicle. Each manufacturer shall, upon request from the 
National Highway Traffic Safety Administration, provide information 
regarding which of the compliance options it has selected for a 
particular vehicle or make/model.
* * * * *

                       Table I.--Stopping Sequence
------------------------------------------------------------------------
                                                                 Single
                                                      Truck       unit
                                                     tractors    trucks
                                                               and buses
------------------------------------------------------------------------
Burnish...........................................          1          1
Stability and Control at GVWR (PFC 0.5)...........          2        N/A
Stability and Control at LLVW (PFC 0.5)...........          3          5
Manual Adjustment of Brakes.......................          4        N/A
60 mph Service Brake Stops at GVWR (PFC 0.9)......          5          2
60 mph Emergency Service Brake Stops at GVWR (PFC         N/A          3
 0.9).............................................
Parking Brake Test at GVWR........................          6          4
Manual Adjustment of Brakes.......................          7          6
60 mph Service Brake Stops at LLVW (PFC 0.9)......          8          7
60 mph Emergency Service Brake Stops at LLVW (PFC           9          8
 0.9).............................................
Parking Brake Test at LLVW........................         10          9
Final Inspection..................................         11         10
------------------------------------------------------------------------

* * * * *

    Issued on July 31, 2003.
Jeffrey W. Runge,
Administrator.
[FR Doc. 03-20025 Filed 8-8-03; 8:45 am]
BILLING CODE 4910-59-P