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MAINTENANCEMAINTENANCE
Tire Labeling
The tires that came on your vehicle have a number of markings. Those you should be
aware of are described below.
Here is an example of what each marking means:
• P235/60R18 102V
•
P: vehicle type (passenger)
•
235: tire width in millimeters
•
60: aspect ratio (tire section height as a percentage
of its width)
•
R: tire construction code (radial)
•
18: rim diameter in inches
•
102: load index (code indicating maximum load tire can
carry)
•
V: speed symbol (code indicating maximum speed
rating)
Example Tire size
Tire
Identi cation
Number (TIN)
Ma ximum
ti re load
Maximum
tire pressure
Tire siz e
n Tire Identification Number (TIN)
The tire identification number (TIN) is a gr
oup of
numbers and letters that look like the example shown.
TIN is located on the sidewall of the tire.
DOT B97R FW6X 2209
DOT: This indicates that the tire meets all
requirements of the U.S. Department of
Transportation.
B97R: Manufacturer’s identi cation mark.
FW 6X: Tire type code.
22 09: Date of manufacture.
Year
Week
n Glossary of Tire Terminology
Cold Tire Pressure – The tire air pressure when the vehicle has been parked for at
least three hours or driven less than 1 mile (1.6 km).
Load Rating – The maximum load that a tire is rated to carry for a given inflation
pressure.
Maximum Inflation Pressure – The maximum tire air pressure that the tire can
hold.
Maximum Load Rating – The load rating for a tire at the maximum permissible
inflation pressure for that tire.
Recommended Inflation Pressure – The cold tire inflation pressure recommended
by the manufacturer.
Treadwear Indicators (TWI) – The projections within the principal grooves
designed to give a visual indication of the degrees of wear of the tread.
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MAINTENANCEMAINTENANCE
DOT Tire Quality Grading
The tires on your vehicle meet all U.S. Federal Safety Requirements. All tires are also graded for
treadwear, traction, and temperature performance according to Department of Transportation
(DOT) standards. The following explains these gradings.
n
Uniform Tire Quality Grading
Quality grades can be found
where applicable on the tire sidewall between tread shoulder
and maximum section width.
For example:
Treadwear 200
Traction AA
Temperature A
All passenger car tires must conform to Federal Safety Requirements in addition to these
grades.
n
Treadwear
The tr
eadwear grade is a comparative rating based on the wear rate of the tire when tested
under controlled conditions on a specified government test course. For example, a tire
graded 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 may depart significantly from the norm due to variations in driving
habits, service practices, and differences in road characteristics and climate. n
Traction
The traction grades,
from highest to lowest, are AA, A, B, and C. Those grades represent the
tire’s ability to stop on wet pavement as measured under controlled conditions on specified
government test surfaces of asphalt and concrete. A tire marked C may have poor traction
performance.
WARNING: The traction grade assigned to this tire is based on straight-ahead braking
traction tests, and does not include acceleration, cornering, hydroplaning, or peak traction
characteristics.
n
Temperature
The
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 level of performance which all passenger
car tires must meet under the Federal Motor Vehicle 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 established for a tire that is properly
inflated and not overloaded. Excessive speed, underinflation, or excessive loading, either
separately or in combination, can cause heat buildup and possible tire failure.
