Tire Designations; Tire Terminology And Definitions - GMC Yukon Denali 2013 Owner's Manual

10-44 Vehicle Care

Tire Designations

Tire Size
The example shows a typical
passenger vehicle tire size.
Passenger (P Metric) Tire
(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 75, as shown in
item C of the tire illustration, it
would mean that the tire's
sidewall is 75 percent as high as
it is wide.
(D) Construction Code
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
characters represent the load
index and speed rating of the
tire. The load index represents
the load carrying capacity a tire
A two-digit 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
A
:
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
automatic transmission, power
steering, power brakes, power
Diameter of
:
windows, power seats, and air
conditioning.
These
:
Aspect Ratio
of a tire's height to its width.
The amount of
:
The
:
The relationship
: