Tire Designations; Tire Terminology And Definitions - Chevrolet Malibu 2012 Owner's Manual

10-46 Vehicle Care

Tire Designations

Tire Size
The following is an example of
a typical passenger vehicle
tire size.
(A) Passenger (P Metric) Tire
The United States version of
a metric tire sizing system.
The letter P as the first
character in the tire size
means a passenger vehicle
tire engineered to standards
set by the U.S. Tire and Rim
Association.
(B) Tire Width
:
number indicates the tire section
width in millimeters from
sidewall to sidewall.
(C) Aspect Ratio
number that indicates the tire
height to width measurements.
For example, if the tire size
aspect ratio is 60, as shown in
item C of the illustration, it would
mean that the tire's sidewall is
60 percent as high as it is wide.
(D) Construction Code
A letter code is used to 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.
The three digit (E) Rim Diameter
the wheel in inches.
(F) Service Description
These characters represent the
A two digit load index and speed rating
:
of the tire. The load index
represents the load carrying
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
air inside the tire pressing
outward on each square inch
of the tire. Air pressure is
expressed in kPa (kilopascal)
or psi (pounds per square inch).
Diameter of
:
:
The amount of
: