Tire Designations - GMC Sierra 2015 Owner's Manual

Tire Designations

Tire Size
The examples show a typical
passenger vehicle and light
truck tire size.
Passenger (P-Metric) Tire
(1) 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.
(2) Tire Width The three-digit
:
number indicates the tire section
width in millimeters from
sidewall to sidewall.
(3) 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.
(4) Construction Code
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.
(5) Rim Diameter
the wheel in inches.
(6) 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.
A letter
:
(1) Light Truck (LT-Metric)
Tire
of a metric tire sizing system.
The letters LT as the first two
characters in the tire size mean
a light truck tire engineered to
standards set by the U.S. Tire
and Rim Association.
Diameter of
: (2) Tire Width
number indicates the tire section
width in millimeters from
These
:
sidewall to sidewall.
(3) Aspect Ratio
number that indicates the tire
height-to-width measurements.
Vehicle Care
Light Truck (LT-Metric) Tire
The United States version
:
The three-digit
:
A two-digit
:
10-57