Owner’s Manual
Black plate (53,1)
GMC Yukon/Yukon XL Owner Manual - 2012 - CRC - 11/8/11
Vehicle Care 10-53
(E) Rim Diameter: Diameter of
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 capacity a tire
is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
Light Truck (LT‐Metric) Tire
(A) Light Truck (LT‐Metric)
Tire
: The United States version
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.
(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 measurement s.
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
:
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
: Diameter of
the wheel in inches.
(F) Load Range
: Load Range.
(G) Service Description
:
The service description indicates
the load index and speed rating
of a tire. If two numbers are
given as in the example,
120/116, then this represents
the load index for single versus
dual wheel usage (single/dual).
The speed rating is the
maximum speed a tire is
certified to carry a load.