2011 Chevrolet Impala Owner's Manual - Page 315

Vehicle Care GM's exclusive TPC Spec system considers over a dozen critical specifications that impact the overall performance of the vehicle, including brake system performance, ride and handling, traction control, and tire pressure monitoring performance. GM's TPC Spec number is molded onto the tire's sidewall near the tire size. If the tires have an all‐season tread design, the TPC Spec number will be followed by an MS for mud and snow. See Tire Sidewall Labeling on page 10‑43 for additional information. GM recommends replacing tires in sets of four. This is because uniform tread depth on all tires will help keep the vehicle performing most like it did when the tires were new. Replacing less than a full set of tires can affect the braking and handling performance of the vehicle. See Tire Inspection on page 10‑56 and Tire Rotation on page 10‑56 for information on proper tire rotation. 10-59 { WARNING Mixing tires could cause you to lose control while driving. If you mix tires of different sizes, brands, or types (radial and bias-belted tires), the vehicle may not handle properly, and you could have a crash. Using tires of different sizes, brands, or types may also cause damage to the vehicle. Be sure to use the correct size, brand, and type of tires on all wheels. It is all right to drive with the compact spare temporarily, as it was developed for use on the vehicle. See Compact Spare Tire on page 10‑74. { WARNING Tires could explode during improper service. Attempting to mount or dismount a tire could cause injury or death. Only your dealer or authorized tire service center should mount or dismount the tires.