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

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 The three digit
:
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.
(E) Rim Diameter
the wheel in inches.
(F) Service Description
These characters represent
the load index and speed rating
of the tire. The load index
represents the load carrying
A two digit 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).
Accessory Weight
combined weight of optional
accessories. Some examples of
optional accessories are
Diameter of
:
automatic transmission, power
steering, power brakes, power
windows, power seats, and air
:
conditioning.
Aspect Ratio
of a tire's height to its width.
Vehicle Care 10-59
The amount of
:
The
:
The relationship
: