[Federal Register Volume 59, Number 79 (Monday, April 25, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-9916]


[[Page Unknown]]

[Federal Register: April 25, 1994]


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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 575

[Docket No. 94-30, Notice 01]
RIN 2127-AF17

 

Consumer Information Regulations Uniform Tire Quality Grading 
Standards

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

ACTION: Request for comments.

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SUMMARY: The Uniform Tire Quality Grading Standards (UTQGS) require 
tire manufacturers to grade their tires for treadwear, traction, and 
temperature resistance to assist consumers in making informed decisions 
when purchasing passenger car tires. NHTSA is soliciting comments on 
ways in which the agency might propose amending the UTQGS to make the 
quality ratings more meaningful to the tire-buying public.
    In addition, the Administration's Climate Change Action Plan calls 
for DOT, through NHTSA, to establish tire labels measuring the tires' 
impact on fuel economy due to rolling resistance and an information 
program to encourage consumers to purchase aftermarket tires with lower 
rolling resistance. Accordingly, NHTSA requests comments on whether to 
propose amending the UTQGS by adding a rolling resistance grade, either 
while retaining the temperature resistance grade or by substituting the 
rolling resistance for the temperature resistance grade.

DATES: Comments must be received by June 24, 1994.

ADDRESSES: Comments should refer to the docket and notice number set 
forth above and be submitted, preferably in 10 copies, to: Docket 
Section, National Highway Traffic Safety Administration, 400 Seventh 
Street SW., room 5109, Washington, DC 20590. Docket room hours are from 
9:30 a.m. to 4 p.m., Monday through Friday.

FOR FURTHER INFORMATION CONTACT: Mr. Nelson Gordy, Office of Market 
Incentives, Office of the Associate Administrator for Rulemaking, 
National Highway Traffic Safety Administration, 400 Seventh Street SW., 
room 5320, Washington, DC 20590, (202) 366-4797.

SUPPLEMENTARY INFORMATION: Section 203 of the National Traffic and 
Motor Vehicle Safety Act of 1966, 15 U.S.C. 1381, et seq. (Safety Act), 
requires the Secretary of Transportation to prescribe a uniform quality 
grading system for motor vehicle tires. The purpose of the system is to 
assist consumers in making informed decisions when purchasing tires. 
NHTSA implemented that statutory mandate by issuing the UTQGS (49 CFR 
575.104). Those standards, applicable to passenger car tires, require 
motor vehicle and tire manufacturers and tire brand name owners to 
provide consumers with information about their tires' relative 
performance regarding treadwear, traction, and temperature resistance. 
Excluded from the standards are deep tread, winter-type snow tires, 
space-saver or temporary use spare tires, tires with nominal rim 
diameters of 10 to 12 inches, and limited production tires.
    The treadwear, traction, and temperature resistance characteristics 
were chosen by NHTSA for rating under the UTQGS after careful study, 
testing, and consideration of public comments. Those characteristics 
were selected because they provide the best balance of tire properties 
for meaningful evaluation by consumers. Those characteristics interact 
with each other so that improvement of one of them could detract from 
the rating of another. For example, treadwear life can be increased by 
varying the construction compounds to produce a ``harder'' tire. To do 
so, however, would have a negative effect on traction performance. 
Treadwear life could also be increased by adding more rubber to the 
tread. Increased tread depth, however, would increase rolling 
resistance because of the additional friction. That would cause the 
tire to run hotter, thus detracting from its temperature resistance, 
and increase the possibility of tire failure.
    Various problems have been encountered in implementing the UTQGS to 
make them as technically accurate, yet as meaningful and understandable 
to consumers as possible. Many of those problems have been resolved by 
changes in test procedures as the program has evolved. Certain problems 
remain, however, as discussed below.

I. Treadwear

    Treadwear has been one of the graded tire characteristics from the 
inception of the quality grading program (see 33 FR 7261, May 16, 
1968). NHTSA concluded, from consideration of public comments early in 
the program, that consumers were most interested in evaluations of tire 
tread life, traction, and high speed performance. Since that time, 
NHTSA has found that treadwear is understood by the average tire buyer, 
making it one of the more meaningful of the UTQGS ratings.
    In its compliance testing, NHTSA measures treadwear by running the 
tires being tested, called candidate tires, over a 400-mile course of 
public roads near San Angelo, Texas. Candidate tires are first 
``broken-in'' by running them over two circuits of the test course. 
Treadwear measurements are taken after that initial break-in and after 
each 800-mile segment thereafter or, optionally, only at the beginning 
and at the end of the complete 6,400 mile test. The test vehicles' 
wheels are aligned to manufacturers' specifications, correct tire 
pressure is maintained throughout the test, and tire loading is 
maintained at 85 percent of the tires' maximum load ratings. The test 
cars travel in convoys, at posted speed limits, with regular changes of 
drivers and with changes in the positions of the cars and tires.
    Upon completion of the 6,400-mile test, the adjusted wear rate for 
a candidate tire is extrapolated to the point of wearout, which is \1/
16\th inch of tread remaining, and the treadwear grade established. A 
grade of 100 represents a tire capable of achieving approximately 
30,000 miles to the wearout point, as measured on the San Angelo 
course. A tire graded at 150 should achieve approximately 50 percent 
more mileage than the one graded at 100, assuming both are run on the 
same course and under the same conditions. It should be noted, however, 
that tire treadwear grades are not intended to be indicative of a 
tire's actual expected mileage. The tire quality grades are intended as 
indicators of relative, not absolute, performance. The actual mileage a 
tire achieves will depend on many factors, such as geographic location, 
individual driving habits, maintenance of proper tire pressure, load, 
type of road surfaces, climatic conditions, and road configurations.
    NHTSA has noted significant changes in treadwear ratings since the 
UTQGS became fully effective in 1980. Early in the UTQGS program, the 
treadwear grading criteria specified in Sec. 575.104(d)(2) produced 
consistent results. As the years progressed, however, treadwear ratings 
have drifted steadily upward in both manufacturers' and NHTSA's testing 
results to the point that many of the ratings appear to be 
questionable. For example, one brand of tires (brand A) recently tested 
on the San Angelo course resulted in a test grade of 832 which, when 
rounded off to the next lower 20-point increment as required by 49 CFR 
575.104(e)(2)(ix)(F), would be labeled with a treadwear grade of 820. 
That figure suggests a degree of relative superiority in treadwear of 
brand A tires over lower tested brands that appears significantly 
disproportionate to the differences in the likely actual mileage of 
those tires. NHTSA understands that tires are of higher quality, 
perform better and last longer than tires produced even a few years 
ago. Such improvements result from industry developments such as 
improvements in rubber compounds, cord materials, tire designs, and 
tread configurations. The agency does not believe, however, that tires 
have improved to the point suggested by the test results for brand A, 
which suggests that, on the San Angelo course, the tire would last over 
240,000 miles. This situation suggests either that the characteristics 
of the course itself are changing or that other factors as yet 
unidentified are responsible, or both.

Course Monitoring Tires

    As noted above, the wear rates of tires can change on a daily basis 
because of such conditions as road surface, temperature, humidity, and 
precipitation. To compensate for those changes in conditions when 
conducting agency compliance testing, candidate tires are tested 
concurrently with course monitoring tires (CMT). Before 1991, CMTs were 
built to strict NHTSA specifications. Since that time, NHTSA has 
required that CMTs be built to the specifications of the American 
Society for Testing Materials (ASTM) standard E1136. CMTs are specially 
designed to have narrow limits of variability and, in fact, are assumed 
to be invariant among tires of a given batch, or lot.
    CMTs are procured by NHTSA in lots of 500-1500. Whenever a new lot 
is procured, a new base course wear rate (BCWR) is established for that 
lot. This is accomplished by treating the new CMT as a candidate tire 
and determining its adjusted wear rate in the same manner prescribed in 
Sec. 575.104 for candidate tires. The new CMT is tested in a convoy 
along with the old CMTs. A course severity adjustment factor (CSAF) is 
determined by dividing the BCWR for the old CMTs by the wear rate of 
the old CMTs in the test. The wear rate of the new CMT in the convoy is 
then multiplied by the CSAF to obtain the adjusted wear rate of the new 
CMT which then becomes the BCWR for the new CMTs.
    Once the BCWR for a new lot of CMTs is established, those new CMTs 
can then be used to grade candidate tires. Upon completion of the 
6,400-mile test, the BCWR is divided by the average wear rate of the 4 
new CMTs in the test convoy to determine the course severity adjustment 
factor. That factor is then applied to the wear rates of the candidate 
tires being graded in the same convoy. The adjusted wear rate of the 
candidate tire is then extrapolated to the point of wearout (\1/16\th 
inch tread remaining) which is then converted to the treadwear rating 
for that tire.
    NHTSA has noted over the years that significant changes have 
occurred in the BCWRs. Although the actual measured treadwear rates of 
CMTs have varied from 3.27 to 6.96 mils per 1,000 miles since 1975, the 
adjusted BCWRs have steadily decreased from 4.44 in 1975 to 1.56 in 
1992, as shown in Table 1, as follows:

                     Table 1.--CMT Wear Rates and Base Course Wear Rate Adjustment Factors                      
----------------------------------------------------------------------------------------------------------------
                                                                                         Wear rate              
                                                                                         (mils per              
          Year tested                       Manufacturer                   Series          1,000         BCWR   
                                                                                           miles)               
----------------------------------------------------------------------------------------------------------------
1975...........................  Goodyear...........................  Batch 1.........         4.44         4.44
1979...........................  Goodyear...........................  Batch 1.........         4.08             
1979...........................  Goodyear...........................  Batch 2.........         3.82         4.16
1980...........................  Goodyear...........................  Batch 2.........         5.29             
1980...........................  Goodyear...........................  Batch 3.........         4.76         3.74
1984...........................  Goodyear...........................  Batch 3.........         4.22             
1984...........................  Uniroyal...........................  40000...........         3.27         2.89
1987...........................  Uniroyal...........................  40000...........         5.96             
1987...........................  Uniroyal...........................  71000...........         4.56         2.21
1989...........................  Uniroyal...........................  71000...........         5.01             
1989...........................  Uniroyal...........................  91000...........         4.84         2.14
1991...........................  Uniroyal...........................  91000...........         6.24             
1991...........................  ASTM E1136.........................  010000..........         4.94         1.70
1991...........................  ASTM E1136.........................  010000..........         6.96             
1992...........................  ASTM E1136.........................  110000..........         6.65         1.62
1992...........................  ASTM E1136.........................  110000..........         5.83             
1992...........................  ASTM E1136.........................  210000..........         5.60         1.56
1993...........................  ASTM E1136.........................  210000..........         7.21             
1993...........................  ASTM E1136.........................  310000..........         6.80         1.47
----------------------------------------------------------------------------------------------------------------

    The BCWR and the actual wear rate theoretically should correlate 
reasonably well. Any differences may be due to climatic variations, 
changes in course severity, non-uniformity of wear rates between 
individual tires within the same lot, effects of aging and storage on 
the wear rates of the CMTs, errors in the calculation for adjusting 
BCWRs, or perhaps some combination of those factors.
    The test course is well maintained by the State of Texas and does 
not appear to have changed appreciably since testing first started 
there in 1975. That suggests that a significant part of the change in 
BCWRs may be attributed to the CMTs instead of course variability. 
NHTSA has noted that in every case in which one lot of CMTs is replaced 
by another, the new lot invariably shows a lower BCWR than the former.
    The first batch of CMTs were procured from Goodyear Tire and Rubber 
Company in 1975 and had a wear rate of 4.44. Tires from that same lot 
were tested again in 1979 and showed a wear rate of 4.08. A new CMT 
batch was purchased in 1979 which showed a wear rate of 3.82. By 1980, 
however, tires tested from that batch showed an increased wear rate of 
5.29. In each batch, the wear rate varied when tested at a later date, 
from one to four years after purchase.
    A possible explanation for those changes in wear rate among tires 
in the same lot could be attributed to aging and/or environmental 
degradation of the tires. To minimize those factors, the agency now 
purchases a one-year supply of CMTs at a time and stores them in the 
basement area of a warehouse which is typically 20 degrees cooler than 
ambient summer temperature.
    In addition to the aging/environmental degradation of CMTs 
affecting the BCWR, the agency believes that the method of calculating 
the BCWR may be in error. As stated above, the purpose of using a CMT 
is to provide a common baseline for all candidate tires. However, it 
appears that the practice of relating all new CMTs to all prior CMTs by 
the procedure described above has somehow distorted the treadwear 
grading procedure to the point that treadwear grades of candidate tires 
are now highly suspect.
    If, instead of utilizing the BCWR to establish treadwear grades, 
the wear rates of the CMTs were compared directly to those of the 
candidate tires to determine the projected mileage of the candidate 
tires, much lower and perhaps more realistic grades would result. In 
the case of the previous example, the average wear rate for these 
candidate tires was 4.90 mils per 1,000 miles when tested. For the CMTs 
that accompanied these tires, with the same convoy, the average wear 
rate was 6.49 mils per 1,000 miles. The actual wearout rate for radial 
CMTs tested in 1975 was 67,000 miles, which is equivalent to a grade of 
223. By assuming that the wearout for the CMTs remains the same, the 
calculated wearout for the tires in question would be 88,700 miles 
(6.49/4.90 x 67,000). This would be equivalent to a grade of 295 or 280 
when rounded off to the nearest lower 20-point increment.
    The direct comparison of wear rates between CMTs and candidate 
tires may produce lower and more realistic grades for tires. It would, 
however, change the original intent of the CMT, which was to provide a 
common baseline for comparison, regardless of when a candidate tire is 
tested. Further, it would present a problem for the marketing of tires 
that are already graded and still in production. Nevertheless, 
improvement in the treadwear grading procedure appears to be needed in 
order to provide treadwear grades that are realistic, consistent, and 
meaningful to consumers.

II. Traction

    Traction grades are established on test pads also located at San 
Angelo, Texas. Two surfaces are used in the test: wet asphalt and wet 
concrete. A test trailer is equipped with ASTM E501 standard tires 
utilized in the tests as control tires. Two standard tires are inflated 
to 24 pounds per square inch (psi), statically balanced, allowed to 
cool to ambient temperature (with inflation pressure readjusted as 
necessary), and mounted on the test trailer. Each tire is then loaded 
to 1,085 pounds. The trailer is towed by a light truck over the wet 
asphalt surface at a speed of 40 miles per hour (mph). One wheel is 
locked, and the locked-wheel traction coefficient is recorded for that 
wheel for a period of 0.5 to 1.5 seconds after lockup. The test is then 
repeated on the wet concrete surface, locking the same wheel. Those 
procedures are repeated 10 times on each surface for each wheel. The 20 
measurements taken on each surface are averaged to find the standard 
traction coefficient for each surface. Those standard traction 
coefficients are then utilized to determine the adjusted traction 
coefficients of the candidate tires.
    Two candidate tires of the same construction type, manufacturer, 
line, and size designation are prepared and tested utilizing the same 
test procedures described above for the standard tires, except that the 
candidate tires are loaded to 85 percent of the test loads specified in 
Sec. 575.104(h). The adjusted traction coefficients of the candidate 
tires are determined in accordance with Sec. 575.104(f)(2) (ix) and 
(x).
    Once tested, candidate tires are assigned grades ``A'', ``B'', or 
``C''. A tire that achieved a high level of performance on both asphalt 
(above 0.47) and concrete (above 0.35) is graded 
``A''. A tire achieving at least medium performance on both surfaces is 
graded ``B'' (above 0.38 on asphalt and above 0.26 on 
concrete). A tire achieving relatively low performance on either or 
both surfaces (below 0.38 on asphalt or below 0.26 on 
concrete) is graded ``C''. From examining traction test data, NHTSA has 
observed that while nearly all tires achieve high traction values on 
the wet asphalt surface, very few achieve high values on the wet 
concrete surface.
    NHTSA conducted a statistical analysis of the traction test data 
since 1989 to determine the frequency distribution of the traction 
coefficients of tires tested on both surfaces. The analysis showed that 
the arithmetic mean of the traction coefficients of tires on the wet 
asphalt surface was 0.51, and the standard deviation was 
0.03. Assuming a normal distribution (in a normal 
or bell-shaped distribution, one standard deviation on both sides of 
the arithmetic mean represents 68.27% of the values included within the 
limits indicated (see ``Statistical Methods,'' by Arkin and Colton, 4th 
Ed. (Rev.), 1958, pages 37 and 38)), it follows that approximately 68 
percent of the tires tested on the asphalt surface would have a 
traction coefficient greater than 0.48, but less than 
0.54. The arithmetic mean of traction coefficients of tires 
tested on the wet concrete surface was 0.38, 
0.03, indicating that approximately 68 percent of 
the tires tested on the wet concrete surface would have a traction 
coefficient greater than 0.35, but less than 0.41.
    That analysis suggests that tire traction has improved to the point 
that it may be appropriate to upgrade the standard by raising the 
minimum traction values for each category. For example, an ``A'' rating 
could call for a traction coefficient above 0.54 on asphalt 
and above 0.41 on concrete; a ``B'' rating could be above 
0.48 on asphalt and above 0.35 on concrete; and for 
``C'', below 0.48 on asphalt and below 0.35 on 
concrete. Alternatively, a new category ``AA'' could be created, the 
lower limit of which could be 0.54 for asphalt and 
0.41 for concrete, with the ``A'', ``B'', and ``C'' categories 
remaining as they are. Either of these alternatives would result in a 
more balanced distribution of tires among grades ``A'', ``B'', and 
``C''.
    Another area of increasing concern in traction testing is the 
possible use of a peak tire traction category for testing rather than 
the sliding traction presently measured.
    Contemporary vehicles are increasingly utilizing anti-lock brakes 
where sliding traction is not the primary traction force in panic 
braking. Those vehicles rely on peak tire traction, that is, maximum 
braking action is obtained when the tire is still rolling. Although 
peak tire traction may be desirable information for consumers with 
vehicles equipped with anti-lock brakes, high peak traction may 
compromise other tire characteristics such as degradation of traction 
when cornering. If peak traction performance of tires differs 
substantially from sliding traction, an alternative traction grading 
procedure may be necessary. NHTSA needs additional data on the 
measurement of peak traction coefficients and on the correlation of 
peak traction coefficients with stopping distance, which may be 
available from commenters. The agency is soliciting any such data.

III. Temperature Resistance

    The temperature resistance grade is intended to indicate the extent 
to which heat is generated and/or dissipated by a given tire, and the 
capability of the tire to withstand the resulting temperature without 
failure. The heat that is generated depends on the amount of energy 
absorbed by the tire in the flexing of the rubber and its reinforcing 
materials. That energy is wasted and appears in the tire as heat. The 
more energy wasted, the greater the amount of heat that is generated 
and, if the tire is not capable of dissipating that greater amount of 
heat and/or if the tire is not able to resist the effects of the higher 
operating temperature that results from that greater amount of heat, 
the lower the temperature resistance grade.
    Heat buildup in tires is generally caused by vehicle overloading, 
high speed operation, and/or tire underinflation. Sustained high 
temperature can cause structural degeneration of the material of the 
tire and result in reduced tire life or potential catastrophic tire 
failure. A tire's resistance to temperature buildup is graded under the 
UTQGS as ``A'', ``B'', or ``C'', with ``A'' being the best and ``C'' 
being the minimum standard of performance. Tires of high quality, as a 
result of superior design and construction, can be expected to last 
longer without failure when subjected to sustained high speed 
operation.
    NHTSA tests tires for temperature resistance using the same 
laboratory test wheel utilized in testing a tire's high speed 
performance under Federal Motor Vehicle Safety Standard (FMVSS) No. 
109, New Pneumatic Tires. The high speed performance test under FMVSS 
109 is run at speeds of up to 85 mph. The temperature resistance test 
under the UTQGS, however, is run at speeds of up to 115 mph. A tire 
graded ``A'' has successfully completed the test procedure at a 
sustained speed of 115 mph on the test wheel. A grade of ``B'' means 
that the tire has successfully completed the test procedure at speeds 
between 100 mph and 115 mph; and a ``C'' grade indicates satisfactory 
completion of the test at speeds exceeding 85 mph but at or below 100 
mph. Of the 2,100 tires graded in 1993, 30 percent were graded ``C'', 
50 percent were graded ``B'', and 20 percent were graded ``A''.
    NHTSA considers temperature resistance a valid safety concern and 
is unaware of any problems with the ratings. While important from a 
motor vehicle safety standpoint, however, the significance of 
temperature resistance is not so widely understood by consumers as the 
treadwear and traction ratings.
    In light of this fact, and recent interest in a rolling resistance 
grade, the agency is considering whether a rolling resistance grade 
could provide equivalent safety information to the temperature 
resistance grade and thereby negate the need for temperature resistance 
grading. The issue of a rolling resistance grade arose at the White 
House Conference on Global Climate Change on June 10 and 11, 1993.
    At the White House Conference, a number of measures to reduce 
greenhouse gasses were discussed. One of the many measures related to 
vehicle fuel economy was the increased use of low rolling resistance 
tires in the aftermarket. Michelin presented a paper on that issue at a 
meeting of the Auto and Light Truck Workshop of the Transportation 
Working Group of the White House Conference on Global Climate Change on 
July 1, 1993. Michelin asserted that the average rolling resistance for 
all-season radial original equipment manufacturer (OEM) tires was 22.6 
percent less than that for all-season radial replacement tires. 
Further, if replacement tires had the same rolling resistance as OEM 
tires, a 4 percent overall improvement in fuel economy could be 
realized. Finally, Michelin announced a manufacturing process by which 
low rolling resistance tires could be produced with no increase in 
inflation pressures.
    As a result of the conference, the Administration issued a report 
on a series of initiatives to reduce greenhouse gas emissions, entitled 
The Climate Change Action Plan, on October 19, 1993. Among other 
things, the Plan calls for reduction of U.S. greenhouse gas emissions 
to 1990 levels by the year 2000. The Plan contains nearly 50 
initiatives to accomplish that goal. One of those initiatives calls for 
DOT, through NHTSA, to issue new rules and test procedures requiring 
tire manufacturers to test and label tires relative to their rolling 
resistance.
    This request for comments is part of NHTSA's commitment to The 
Climate Change Action Plan. Because the UTQGS are not applicable to 
truck tires, NHTSA's Office of Research and Development will, in a 
separate but related action, work with truck tire manufacturers and 
truck fleet and owner organizations to promote a voluntary truck tire 
rolling resistance program.
    The agency also notes that one of the factors that causes heat 
generation in tires also causes higher rolling resistance. Indeed, the 
friction resulting from a tire's rolling resistance is the immediate 
cause of heat generation in the tire. Rolling resistance is measured in 
a procedure similar to that used for determining temperature 
resistance. The rolling resistance test consists of running a tire 
under load on a laboratory test wheel. The energy consumed in and 
recovered from running the tire is measured and the difference is the 
heat energy lost which is a measure of rolling resistance. The smaller 
the difference, the more fuel efficient the tire.
    Since rolling resistance and temperature resistance are related and 
are measured by similar tests, it is necessary to determine whether any 
safety benefits would be lost by substituting rolling resistance for 
temperature resistance in the UTQGS. FMVSS No. 109 would continue to 
ensure that all tires are capable of operating safely at speeds up to 
85 mph, thereby establishing a minimum safety threshold. Further, fuel 
efficiency could be expected to generate more interest and be more 
easily understood by consumers than temperature resistance, thereby 
enhancing the usefulness of the UTQGS to the consumers it is intended 
to assist. However, the agency requests comments on this issue.
    NHTSA believes that there is a strong relationship between rolling 
resistance and fuel consumption. Rolling resistance data generated 
under existing SAE test procedures could be used for quantifying the 
correlation with fuel consumption. SAE Recommended Practices J1269 and 
J1270 specify rolling resistance measurement procedures for passenger 
car tires. The agency would welcome data that could be used to 
demonstrate how reductions in tire rolling resistance values translate 
into improvements in ``real world'' fuel economy.

IV. Issues for NHTSA Evaluation

    As stated above, the objective of the UTQGS is to provide 
meaningful, comparative information to consumers that will assist them 
in making informed selections when purchasing passenger car tires. In 
addition, the UTQGS should stimulate competitive forces in the 
marketplace, resulting in better tire performance. By improving the 
UTQGS, NHTSA believes it can achieve those goals.
    The agency is hopeful, therefore, that this notice will elicit 
useful comments and suggestions on the UTQGS issues discussed above. 
NHTSA's major concerns are whether to propose changes to deal with 
treadwear grades that are becoming extremely high and therefore of 
diminishing credibility; whether to propose raising the thresholds for 
traction grades; and whether it is more appropriate under the National 
Traffic and Motor Vehicle Safety Act for the agency to propose adding 
rolling resistance to the UTQGS as a fourth grading category or 
substituting it for temperature resistance. NHTSA specifically requests 
comments on the following issues:
    1. Does the existing system for measuring treadwear result in 
misleading grades? Why?
    2. Should a new system be developed for establishing treadwear 
grades? What system?
    3. Should the treadwear test procedure be changed? What specific 
changes should be made? Why? What data are available to support such 
changes? How should such changes be implemented?
    4. Should the test course calibration procedure be changed? What 
changes should be made?
    5. How should traction grades be determined or improved? Does 
traction change significantly with wear for any tire lines?
    6. Should the traction grades be upgraded? By raising the minimum 
values for each category (A, B, C)? By creating a new category, such as 
``AA''? By other means?
    7. Should the UTQGS include peak tire traction ratings? Does peak 
tire traction correlate with stopping distance on ABS-equipped 
vehicles? Can the peak tire traction coefficient be measured reliably? 
How could/should it be expressed?
    8. What would be the cost of measuring peak traction? In addition 
to sliding traction? Instead of sliding traction?
    9. Are the characteristics related to a tire's ability to dissipate 
heat and to withstand higher operating temperatures that affect a 
tire's temperature resistance rating directly related to a tire's 
rolling resistance?
    10. Should the temperature resistance grade be deleted from the 
UTQGS? Is it adequately represented by the voluntary tire industry 
speed ratings?
    11. Should a rolling resistance grade replace temperature 
resistance? How would such a grade be expressed? How would it be 
labeled on the tire?
    12. Should a rolling resistance grade be added to the UTQGS as a 
fourth category?
    13. How would the agency explain to consumers the correlation 
between rolling resistance and fuel economy?
    14. Can rolling resistance be improved without detracting from the 
other graded characteristics? What is the additional cost per tire? Do 
you agree with the costs projected in The Climate Change Action Plan?
    15. Can tires of the same size, construction, and load carrying 
capacity which have the same rolling resistance, exhibit significantly 
different temperature resistance performance?
    16. Would any safety values be affected if rolling resistance 
replaced temperature resistance?
    17. How should data based on the test procedures of SAE-J1269 and 
SAE-J1270 be utilized to compare the rolling resistance performance of 
different tires?
    18. What data regarding rolling resistance of different tire 
designs currently exist?
    19. What is the range of rolling resistance performance available 
both to OEM and aftermarket passenger car tires today? What is the 
potential for further reductions in rolling resistance for tires of 
various types, such as all-season, mud/snow, rain, and conventional?
    20. Are there improvements that should be made in the current 
procedures for measuring rolling resistance? If so, please describe how 
those measures could be improved, and at what additional cost.
    21. What should be done about tires already graded?
    22. What would be the most effective campaign to publicize the low 
rolling resistance/fuel efficiency program?
    23. What procedures would be most effective in monitoring the low 
rolling resistance/fuel efficiency program to assure maximum results?
    24. What is the estimated incremental consumer cost increase for 
low rolling resistance tires of various types?
    25. What is the estimated cost effectiveness for low rolling 
resistance tires of various types? How cost effective would low rolling 
resistance tires have to be to motivate consumers to buy them?
    26. What is the current cost of tire labeling for treadwear, 
traction, and temperature resistance combined on a per tire basis, 
assuming a high volume production line? How would this cost change if 
rolling resistance replaced temperature resistance? If it were added, 
without replacing any of the existing UTQGS requirements?
    27. What are current equipment and per test costs to measure 
temperature resistance according to UTQGS? Rolling resistance according 
to SAE guidelines?
    28. Is it necessary to replace all 4 tires to achieve the benefits 
of lower rolling resistance tires? What are the fuel savings if fewer 
than 4 tires are replaced?
    29. What is the frequency with which consumers replace 4 tires at 
once? Three tires? Two tires?
    30. Are there other or additional measures NHTSA should consider to 
aid in reducing greenhouse gasses? What are the costs and benefits of 
these measures?

V. Rulemaking Analyses and Notices

A. Executive Order 12866 (Regulatory Analysis and Review) and DOT 
Regulatory Policies and Procedures.

    This notice was not reviewed under E.O. 12866. NHTSA has considered 
the impacts associated with this request for comments and has concluded 
that it is not significant under DOT's Regulatory Policies and 
Procedures. As explained above, this document requests comments to aid 
the agency in determining whether to propose improvements in the UTQGS 
and whether to propose either adding a rolling resistance grade or 
substituting a rolling resistance grade for the currently-required 
temperature resistance grade. Improvements in the UTQGS would make them 
more meaningful and understandable to consumers and contribute to 
energy conservation in accordance with the President's Climate Change 
Action Plan.

B. Executive Order 12612 (Federalism)

    NHTSA has analyzed this action under the principles and criteria of 
E.O. 12612. The agency has determined that this request for comments 
does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.

VI. Comments

    Interested persons are invited to submit comments. It is requested, 
but not required, that comments be submitted in 10 copies.
    Comments must not exceed 15 pages in length (49 CFR 553.21). 
Necessary attachments may be appended to such submissions without 
regard to the 15-page limit. This limitation is intended to encourage 
commenters to state their primary arguments in a concise fashion.
    All comments are retained in the NHTSA Docket Section and are open 
and available to the public for review and copying. If a commenter 
wishes to submit certain information under a claim of confidentiality, 
3 copies of the complete submission, including the business information 
for which confidentiality is requested, should be submitted to the 
Chief Counsel, NHTSA, at the address shown above. Seven copies from 
which the purportedly confidential business information has been 
deleted should be submitted to the NHTSA Docket Section. A request for 
confidentiality should be accompanied by a cover letter setting forth 
the information specified in 49 CFR part 512, Confidential Business 
Information.
    Those commenters desiring to be notified upon receipt of their 
comments in the NHTSA Docket Section should enclose a self-addressed 
stamped postcard in the envelope with their comment. Upon receipt of 
the comment in the Docket Section, the docket supervisor will return 
the postcard by mail.

List of Subjects in 49 CFR Part 575

    Consumer Information Regulations: Vehicle stopping distance, Truck-
camper loading, Uniform tire quality grading standards, Utility 
vehicles.

    Issued on April 20, 1994.
Barry Felrice,
Associate Administrator for Rulemaking.
[FR Doc. 94-9916 Filed 4-22-94; 8:45 am]
BILLING CODE 4910-59-P