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Tire Information (U.S.A.)
P215/65R15 95H is an example of a tire size and load index rating. Here \
is an explanation
of the various components of that tire size and load index rating. Note that the tire size and
load index rating may be different from the example.
P
Indicates a tire that may be installed on cars, SUVs, minivans and light trucks as designated
by the Tire and Rim Association (T&RA).
NOTE
If your tire size does not begin with a letter this may mean it is designated by ei\
ther ETRTO
(European Tire and Rim Technical Organization) or JATMA (Japan Tire Manufacturing
Association).
215
“215” is the nominal width of the tire in millimeters. This three-digit number gives the
width in millimeters of the tire from sidewall edge to sidewall edge. In\
general, the larger
the number, the wider the tire.
65
“65” is the aspect ratio. This two-digit number indicates the tire's ratio of height to width.
R
“R” is the tire construction symbol. R indicates “Radial ply co\
nstruction”.
15
“15” is the wheel rim diameter in inches.
95
“95” is the Load Index. This two-or three-digit number indicates how much weight each tire
can support.
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Tire Information (U.S.A.)
Maximum Permissible Inflation Pressure
This number is the greatest amount of air pressure that should ever be p\
ut in the tire under
normal driving conditions.
Tread Wear, Traction and Temperature Grades
Tread wear: The tread wear grade is a comparative rating based on the wear rate of t\
he 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 c\
ontrolled 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. M\
ake
sure you purchase snow tires that are the same size and construction typ\
e as the other tires
on your vehicle.
SAFETY WARNING
The following safety warning appears on the tire's sidewall.
SERIOUS INJURY MAY RESULT FROM:
EXPLOSION 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. TIRE 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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Tire Information (U.S.A.)
Glossary 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 whic\
h they replace,
and not previously considered in the curb weight or accessory weight, in\
cluding 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 u\
pon which the tire
beads are seated.
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Tire Information (U.S.A.)
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:
Tires not of the designated size Tires of different sizes or types at the same time 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.
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 T
read wear indicator
Worn tread
You should replace the tire before the band crosses the entire tread.
(With tire pressure monitoring system)
After adjusting the tire pressure, initialization of the tire pressure m\
onitoring system is
necessary to make the system operate normally.
Refer to Tire Pressure Monitoring System Initialization on page 4-96.
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