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Tread Wear, Traction and Temperature 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 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.
Traction: The traction grades, from highest to lowest are AA, A, B, and C. The 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.
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.
Snow Tires
In some heavy snow areas, local governments may require true snow tires, those with very
deeply cut tread. These tires should only be used in pairs or placed on all four wheels.
Make sure you purchase snow tires that are the same size and construction type as the other
tires on your vehicle.
SAFETY WARNING
The following safety warning appears on the tire's sidewall.
SERIOUS INJURY MAY RESULT FROM:
lEXPLOSION OF TIRE/RIM ASSEMBLY DUE TO IMPROPER MOUNTING-
MATCH TIRE DIAMETER TO RIM DIAMETER; NEVER EXCEED 40 psi (275 kPa)
TO SEAT BEADS-ONLY SPECIALLY TRAINED PERSONS SHOULD MOUNT
TIRES.
lTIRE FAILURE DUE TO UNDER-INFLATION/OVERLOADING/DAMAGE-
FOLLOW OWNER'S MANUAL AND PLACARD IN VEHICLE-FREQUENTLY
CHECK INFLATION PRESSURE AND INSPECT FOR DAMAGE.
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qGlossary of Terms
Tire Placard: A label indicating the OE tire sizes, recommended inflation pressure, and
the maximum weight the vehicle can carry.
Tire Identification Number (TIN): A number on the sidewall of each tire providing
information about the tire brand and manufacturing plant, tire size, and date of
manufacture.
Inflation Pressure: A measure of the amount of air in a tire.
kPa: Kilopascal, the metric unit for air pressure.
psi: Pounds per square inch, the English unit for air pressure.
B-pillar: The structural member at the side of the vehicle behind the front door.
Original Equipment (OE): Describes components originally equipped on the vehicle.
Vehicle Load Limit: The maximum value of the combination weight of occupants and
cargo.
Bead Area of the Tire: Area of the tire next to the rim.
Sidewall Area of the Tire: Area between the bead area and the tread.
Tread Area of the Tire: Area on the perimeter of the tire that contacts the road when it's
mounted on the vehicle.
Seating capacity means the total allowable number of vehicle occupants. Seating capacity
is described on the tire label.
Production options weight is the combination weight of installed regular production
options weighing over 2.3 kilograms in excess of the standard items which they replace,
and not previously considered in the curb weight or accessory weight, including heavy
duty brakes, ride levelers, roof rack, heavy duty battery, and special trim.
Rim is the metal support (wheel) for a tire or a tire and tube assembly upon which the tire
beads are seated.
Customer Information and Reporting Safety Defects
Tire Information (U.S.A.)
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CAUTION
Rotate unidirectional tires and radial tires that have an asymmetrical tread pattern
or studs only from front to rear, not from side to side. Tire performance will be
weakened if rotated from side to side.
(With limited-slip differential)
Don't use the following:
ØTires not of the designated size
Ø Tires of different sizes or types at the same time
Ø Tires not sufficiently inflated
If these instructions aren't followed, the rotation of the left and right wheels will be
different and will thus apply a constant load on the limited-slip differential.
This will cause a malfunction.
q Replacing a Tire
WARNING
Always use tires that are in good condition:
Driving with worn tires is dangerous. Reduced braking, steering, and traction could
result in an accident.
If a tire wears evenly, a wear indicator will appear as a solid band across the tread. Replace
the tire when this happens.
New tread Tread wear indicator
Worn tread
You should replace it before the band is across the entire tread.
NOTE
Tires degrade over time, even when they are not being used on the road. It is recommended that tires
generally be replaced when they are 6 years or older. Heat caused by hot climates or frequent high
loading conditions can accelerate the aging process. Regarding the manufacturing week and year is
indicated with 4 digit. Refer to The tire labeling on page 9-23.
Customer Information and Reporting Safety Defects
Tire Information (U.S.A.)
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