[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
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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
