Maintenance
58
7
Tire terminology and defini-
tions
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 kilo-
pascal (kPa).
Accessory Weight: This means the
combined weight of optional acces-
sories. Some examples of optional
accessories are, automatic transaxle
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 kilo-
pascals (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 des-
ignator 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.
Intended Outboard Sidewall: The
side of an asymmetrical tire, that
must always face outward when
mounted on a vehicle.
Kilopascal (kPa): The metric unit for
air pressure.
WARNING - Tire temperature
The temperature grade for this
tire is established for a tire that
is properly inflated and not
overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
build-up and possible sudden
tire failure. This can cause loss
of vehicle control and serious
injury or death.
