Tire Terminology And Definitions - Pontiac G3 2010 Owner's Manual

(D) Construction Code
indicate the type of ply construction in the tire.
The letter R means radial ply construction; the
letter D means diagonal or bias ply construction;
and the letter B means belted bias ply
construction.
(E) Rim Diameter Diameter of the wheel in
:
inches.
(F) Service Description
represent the load index and speed rating of the
tire. The load index represents the load carry
capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is certified to
carry a load.

Tire Terminology and Definitions

Air Pressure The amount of air inside the tire
:
pressing outward on each square inch of the tire.
Air pressure is expressed in pounds per square
inch (psi) or kilopascal (kPa).
Accessory Weight
:
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
6-54
A letter code is used to
:
These characters
:
This means the combined
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
:
in a tire, measured in pounds per square inch (psi)
or kilopascals (kPa) before a tire has built up heat
from driving. See Inflation - Tire Pressure on
page 6 57.
Curb Weight 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 (DOT)
motor vehicle safety standards. The DOT code
The amount of air pressure