GM Service Manual Online
For 1990-2009 cars only

Object Number: 70080  Size: SH

A Tire Performance Criteria (TPC) specification number is molded in the sidewall near the tire size of all original equipment tires. The specification number assures that the tire meets the following GM performance standards:

    • Traction
    • Endurance
    • Dimension
    • Noise
    • Handling
    • Rolling Resistance, etc.

Usually, each tire size has a specific TPC number assigned. Replacement tires should match the original tires for the following:

    • Same size
    • Same speed rating
    • Same load range
    • Same construction

Replace the original tires with tires of the same TPC specification number. Use of any other tire size or tire type may seriously affect any or all of the following:

    • Affect the ride
    • Affect the handling
    • Affect the speedometer/odometer calibration
    • Affect the vehicle ground clearance
    • Affect the tire clearance to the body and chassis