07 Wheels and tires
Tire designations
07
179
1
2
3
4
5
6
12
11
10
8
79
G026442
Federal law mandates that tire manufacturers
place standardized information on the sidewall
of all tires (see the illustration).
The following information is listed on the tire
sidewall:
The tire designation:
NOTE
Please be aware that the following tire des-
ignation is an example only and that this
particular tire may not be available on your
vehicle.
215: the width of the tire (in millimeters)
from sidewall edge to sidewall edge. The
larger the number, the wider the tire.
65: The ratio of the tire's height to its width
in percent.
R: Radial tire.
15: The diameter of the wheel rim (in
inches).
95: The tire's load index. In this example, a
load index of 95 equals a maximum load of
1521 lbs (690 kg).
H: The tire's speed rating, or the maximum
speed at which the tire is designed to be
driven for extended periods of time, carry-
ing a permissible load for the vehicle, and
with correct inflation pressure. For exam-
ple, H indicates a speed rating of 130 mph
(210 km/h).
NOTE
The tire's load index and speed rating may
not appear on the sidewall because they are
not required by law.
M+S or M/S = Mud and Snow; AT = All
Terrain; AS = All Season
U.S. DOT Tire Identification Number
(TIN): This begins with the letters "DOT"
and indicates that the tire meets all federal
standards. The next two numbers or letters
are the plant code where it was manufac-
tured, the next two are the tire size code
and the last four numbers represent the
week and year the tire was built. For exam-
ple, 1510 means that the tire was manu-
factured during week 15 of 2010. The num-
bers in between are marketing codes used
at the manufacturer's discretion. This infor-
mation helps a tire manufacturer identify a
tire for safety recall purposes.
Tire Ply Composition and Material
Used: Indicates the number of plies indi-
cates or the number of layers of rubber-
coated fabric in the tire tread and sidewall.
Tire manufacturers also must indicate the
ply materials in the tire and the sidewall,
which include steel, nylon, polyester, and
others.
Maximum Load: Indicates the maximum
load in pounds and kilograms that can be
carried by the tire. Refer to the vehicle's tire
information placard located on the B-Pillar
or the driver's door for the correct tire pres-
sure for your vehicle.
07 Wheels and tires
Uniform Tire Quality Grading
07
183
ALL PASSENGER VEHICLE TIRES MUST
CONFORM TO FEDERAL SAFETY
REQUIREMENTS IN ADDITION TO THESE
GRADES
Quality grades can be found, where appli-
cable, on the tire sidewall between the tread
shoulder and maximum section width. For
example:
Treadwear 200 Traction AA Temperature A
TREADWEARThe treadwear 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 example, a tire gra-
ded 150 would wear one and one half (1 1/2)
times as well on the government course as a
tire graded 100. The relative performance of
tires depends upon the actual conditions of
their use, however, and many depart signifi-
cantly from the norm due to variation in driving
habits, maintenance practices and differences
in road characteristics and climate.
TRACTIONThe traction grades, from highest to lowest, are
AA, A, B, and C, as measured under controlled
conditions on specified government test sur-
faces of asphalt and concrete. A tire marked C
may have poor traction performance.
WARNING
The traction grade assigned to this tire is
based on braking (straight-ahead) traction
tests and is not a measure of cornering
(turning) traction.
TEMPERATUREThe temperature grades are A (the highest), B,
and C, representing the tire's resistance to the
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
material of the tire to degenerate and reduce
tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds
to a minimum level of performance that all pas-
senger vehicle tires must meet under the Fed-
eral Motor Safety Standard No. 109. Grades B
and A represent higher levels of performance
on the laboratory test wheel than the minimum
required by law.
WARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, under-
inflation, or excessive loading, either sepa-
rately or in combination, can cause heat
buildup and tire failure.
