Hummer H2 2009 Owner's Manual page 413

(F) Tire Ply Material
:
number of plies in the sidewall and under
the tread.
(G) Single Tire Maximum Load
that can be carried and the maximum pressure
needed to support that load when used as a
single. For information on recommended
tire pressure see Inflation - Tire Pressure on
page 5-63 and Loading the Vehicle on page 4-44.
Tire Size
The following illustration shows an example of a
typical passenger vehicle tire size.
Light Truck (LT-Metric) Tire
(A) Light Truck (LT-Metric) Tire
States version of a metric tire sizing system. The
letters LT as the first two characters in the tire size
means a light truck tire engineered to standards set
by the U.S. Tire and Rim Association.
The type of cord and
Maximum load
:
The United
:
(B) Tire Width The three-digit number indicates
:
the tire section width in millimeters from sidewall
to sidewall.
(C) Aspect Ratio A two-digit 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 light truck (LT-Metric) tire
illustration, it would mean that the tire's sidewall is
75 percent as high as it is wide.
(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
indicates the load range and speed rating of a
tire. The load index can range from 1 to 279.
Speed ratings range from A to Z.
A letter code is used to
:
The service description
:
5-59