Wheels
with all-season or winter tires, which offer better
traction under those cond itions. We suggest you
use the recommended snow or all-season tires
specified for your vehicle, or their equivalent.
Refer to
q page 342 for more detailed informa
tion regarding winter tires.
Uniform tire quality grading
-Tread wear
- Traction AA A B C
- Temperature ABC
Quality grades can be found where applicable on
the tire side wall between tread shoulder and
maximum sect ion w idth
q page 328, fig. 278.
For example: Tread wear 200 , Traction AA, Tem
perature
A .
All passenger car tires must conform to Federal
Safety Requirements in addition to these grades.
Tread wear
The tread wear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified gov
ernment test course .
For examp le, a tire graded 150 would wear one
and one half
(1 1/2) times as well on the govern
ment course as a tire graded 100.
The relative performance of tires depends upon
the actual conditions of their use, however, and
may depart significantly from the norm due to
variations in driving habits, service practices and
differences in road characteristics and climate.
Traction
The traction grades, from highest to lowest, are
AA, A, Band
C. Those grades represent the tire 's
ability to stop on wet pavement as measured un
der controlled conditions on specified govern
ment test surfaces of asphalt and concrete . A tire
marked C may have poor traction performance
q .,&..
Temperature
The temperature grades are A (the highest), B,
and C, representing the tire's resistance to the
344
generation of heat and its ability to dissipate
heat when tested under controlled conditions on
a specified indoor laboratory test wheel.
Sustained high temperature can cause the mate
rial of the tire to degenerate and reduce tire life,
and excessive temperature can lead to sudden
tire
failure ¢.&. .
The grade C corresponds to a level of perform
ance which all passenger car tires must meet un
der the Federal Motor Vehicle Safety Standard
No. 109. Grades Band A represent higher levels
of performance on the laboratory test wheel than
the minimum required by law.
A WARNING
-
The tract ion grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cor
nering, hydroplaning or peak traction charac
teristics.
A WARNING
The temperature grade for th is tire is estab
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla
tion, or excessive loading, either separately or
in combination, can cause heat bui ldup and
possible tire failure.
A WARNING
Temperature grades apply to tires that are properly inflated and not over or underinflat
ed .
Tire pressure monitoring
system
(1) General notes
App lies to : vehicles with tire pressure mo nitori ng syste m
.
Each tire, including the spare (if provided),
should be checked monthly when cold and inflat
ed to the inflation pressure recommended by the
vehicle manufacturer on the vehicle placard or
tire inflation pressure label. (If your veh icle has
tires of a different size than the size ind icated on
the veh icle placard or tire inflat ion pressure
..,.
