Maintenance
9-38
 WARNING
The temperature grade for this tire is 
established for a tire that is properly 
inflated and not overloaded. 
Excessive speed, under-inflation, 
over-inflation, or excessive loading, 
either separately or in combination, 
can cause heat build-up and 
possible sudden tire failure. This 
may cause loss of vehicle control 
resulting in an accident.
Tire Terminology and Definitions
Air pressure
The amount of air inside the tire 
pressing outward on the tire. Air 
pressure is expressed in pounds per 
square inch (psi) or kilopascal (kPa).
Accessory weight
This means the combined weight 
of optional accessories. Some 
examples of optional accessories 
are automatic transmission, power 
seats, and air conditioning.
Aspect ratio
The relationship of a tire’s height to 
its width.
Belt
A rubber coated layer of cords that 
is located between the plies and the 
tread. Cords may be made from steel 
or other reinforcing materials.
Bead
The tire bead contains steel wires 
wrapped by steel cords that hold the 
tire onto the rim.
Bias ply tire
A pneumatic tire in which the plies are 
laid at alternate angles less than 90 
degrees to the centerline of the tread.
Cold tire pressure
The amount of air pressure in a tire, 
measured in pounds per square inch 
(psi) or kilopascals (kPa) before a tire 
has built up heat from driving.
Curb weight
This means the weight of a motor 
vehicle with standard and optional 
equipment including the maximum 
capacity of fuel, oil and coolant, but 
without passengers and cargo.
DOT markings
A code molded into the sidewall 
of a tire signifying that the tire 
is in compliance with the U.S. 
Department of Transportation motor 
vehicle safety standards. The DOT 
code includes the Tire Identification 
Number (TIN), an alphanumeric 
designator which can also identify 
the tire manufacturer, production 
plant, brand and date of production.
GVWR
Gross Vehicle Weight Rating
GAWR FRT
Gross Axle Weight Rating for the 
Front Axle.
GAWR RR
Gross Axle Weight Rating for the 
Rear axle.