10-50 Vehicle Care
(2) 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.
(3) 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.
DOT Tire Date of
Manufacture
: The last four
digits of the TIN indicate the
tire manufacture d date. The first
two digits represent the week
(01-52) and the last two digits,
the year. For example, the third
week of the year 2010 would
have a four-digit DOT date
of 0310.
(4) Tire Identificatio n 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.
(5) Tire Ply Material
: The type
of cord and number of plies in
the sidewall and under the tread.
(6) 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 10-68.
(7) Maximum Cold Inflation
Load Limit
: Maximum load
that can be carried and the
maximum pressure needed
to support that load. For
information on recommended
tire pressure see Tire Pressure
on page 10-56 and Vehicle Load
Limits on page 9-10.