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Black plate (54,1)
GMC Yukon Denali/Yukon XL Denali Owner Manual - 2011
10-54
Vehicle Care
Tire Designations
Tire Size
The following examples show
the different parts of a 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
:
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% 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) 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.