Useful information about a tire is molded into its sidewall. The examples show a typical passenger tire sidewall.
Passenger (P-Metric) Tire Example
(1) Tire Size: The tire size 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.
(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 manufactured 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 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.
(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 10-52.
(7) Maximum Cold Inflation Load Limit: Maximum load that can be carried and the maximum pressure needed to support that load.
Summer Tires
Tire DesignationsInformation Displays
Driver Information Center (DIC)
The DIC displays information about the vehicle. It also displays warning messages
if a system problem is detected. See Vehicle Messages on page 5-26. All messages
appear in the DIC display in the instrument cluster.
DIC Operation and Displays
The DIC has differ ...
Brake System
Visually inspect brake lines and hoses for proper hook-up, binding, leaks, cracks,
chafing, etc. Inspect disc brake pads for wear and rotors for surface condition.
Inspect drum brake linings/shoes for wear or cracks. Inspect other brake parts,
including drums, wheel cylinders, calipers, parkin ...
Malfunction Indicator Lamp
A computer system called OBD II (On-Board Diagnostics-Second Generation) monitors
the operation of the vehicle to ensure emissions are at acceptable levels, helping
to maintain a clean environment. The malfunction indicator lamp comes on when the
vehicle is placed in ON/RUN, as a check to show ...