Pontiac 2004 Sunfire Owner's Manual page 279

(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) Tire Performance Criteria Specification
(TPC Spec): 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) Department of Transportation (DOT): 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 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 5-60.
(G) Maximum Cold Inflation Load Limit: Maximum
load that can be carried and the maximum pressure
needed to support that load. For more information on
recommended tire pressure see Inflation - Tire Pressure
on page 5-56 and Loading Your Vehicle on page 4-33.
5-51