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P215/65R15 95H is an example of a tire size and load index rating. Here is an explanation
of the various components of tha t 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 ins talled 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 either 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 thr ee-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 t ire'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 indicate s how much weight each tire
can support.
H
“H” is the speed rating. The speed rating denotes the maximum s peed for which the use of
the tire is rated.
Letter Rating Speed Rating
Q9 9 m ph
R1 06 m ph
S 112 mph
T 118 mph
U1 24 m ph
H1 30 m ph
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Traction: The traction grades, from highe st to lowest are AA, A, B, and C. The grades
represent the tire's ability to stop on wet pavement as measure d under controlled conditions
on specified government test surfaces of asphalt and concrete. A tire marked C may have
poor traction performance.
Te m p e r a t u r e : The temperature grades are A (the highest), B and C, represent ing the tire's
resistance to the generation of heat and its ability to dissipa te heat when tested under
controlled conditions on a spec ified indoor laboratory test whe el.
Snow Tires
In some heavy snow areas, local governments may require true sn ow tires, those with very
deeply cut tread. These tires should only be used in pairs or p laced 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 a ppears on the tire's sidewall.
SERIOUS INJURY MAY RESULT FROM:
EXPLOSION OF TIRE/RIM ASSEMBLY DUE TO IMPROPER MOUNTING-MATCH
TIRE DIAMETER TO RIM D IAMETER; 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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▼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 u nit 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 t ire that contacts the road when it's
mounted on the vehicle.
Seating capacity means the total allowable numbe r 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 i tems which they replace, and
not previously considered in the curb weight or accessory weigh t, including heavy duty
brakes, ride levelers, roof rack, heavy duty battery, and speci al trim.
Rim is the metal support (wheel) for a tire or a tire and tube ass embly upon which the tire
beads are seated.
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(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 rotati on of the left and right wheels will be different
and will thus apply a consta nt load on the limited-slip
differential.
This will cause a malfunction.
▼ Replacing a Tire
WA R N I N G
Always use tires that are in good condition:
Driving with worn tires is dangerous. Reduced br
aking, steering, and traction could result in
an accident.
If a tire wears evenly, a wear ind icator 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 the tire before the band crosses 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. The period in which
the tire was manufactured (both week and year) is indicated by a 4-digit number.
Refer to Tire Labeling on page 8-25.
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