Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustration is an example
of a typical P-Metric tire sidewall.
(A) Tire Size
: The tire size code is a combination
of letters and numbers used to define a particular
tire’s width, height, aspect ratio, construction
type, and service description. See the Tire Size
illustration later in this section for more detail.
(B) TPC Spec (Tire Performance Criteria
Specification)
: Original equipment tires designed
to GM’s specific tire performance criteria have a
TPC specification code molded onto the sidewall.
GM’s TPC specifications meet or exceed all federal
safety guidelines.
(C) DOT (Department of Transportation)
:
The Department of Transportation (DOT) code
indicates that the tire is in compliance with the
U.S. Department of Transportation Motor Vehicle
Safety Standards.
(D) Tire Identification Number (TIN)
: The letters
and numbers following the DOT code are the Tire
Identification Number (TIN). The TIN shows the
manufacturer and plant code, tire size, and date the
tire was manufactured. The TIN is molded onto both
sides of the tire, although only one side may have
the date of manufacture.
(E) Tire Ply Material
: The type of cord and
number of plies in the sidewall and under the tread.
(F) Uniform Tire Quality Grading (UTQG)
: Tire
manufacturers are required to grade tires based
on three performance factors: treadwear, traction,
and temperature resistance. For more information,
see Uniform Tire Quality Grading on page 5-62.
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