Pontiac 2004 Bonneville Owner's Manual page 337

(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 5-74.
(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 5-67 and Loading Your Vehicle on page 4-33.
5-61