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MAINTENANCE
MAINTENANCE
Traction devices that are the wrong size or improperly installed can
damage your vehicle’s brake lines, suspension, body, and wheels. Stop
driving if they are hitting any part of the vehicle.
NOTICE
Using the wrong chains or not properly installing chains, can damage the
brake lines and cause a crash in which you can be seriously injured or
killed.
Follow all instructions in this guide regarding the selection and use of tire
chains.
WARNING
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:
P215/55R17 94V
P:
vehicle type (passenger vehicle)
215:
tire width in millimeters
55:
aspect ratio (tire section height
as a percentage of its width)
R:
tire construction code (radial)
17:
rim diameter in inches
94:
load index (code indicating
maximum load tire can carry)
V:
speed symbol (code indicating
maximum speed rating)
Tire size
Tire
identification
number (TIN)
Maximum
tire load
Maximum
tire pressure
Tire size
n
Tire Identification Number (TIN)
The tire identification number
(TIN) is a group 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 identification mark
FW6X: Tire type code
22 09: Date of Transportation
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.
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 treadwear 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.