Buying New TiresGM has developed and matched specific tires for yourvehicle. The original equipment tires installed on yourvehicle, when it was new, were designed to meet GeneralMotors Tire Performance Criteria Specification (TPCSpec) system rating. If you need replacement tires,GM strongly recommends that you get tires with thesame TPC Spec rating. This way, your vehicle willcontinue to have tires that are designed to give thesame performance and vehicle safety, during normaluse, as the original tires.GM’s exclusive TPC Spec system considers over adozen critical specifications that impact the overallperformance of your vehicle, including brake systemperformance, ride and handling, traction control, and tirepressure monitoring performance. GM’s TPC Specnumber is molded onto the tire’s sidewall near the tiresize. If the tires have an all-season tread design, the TPCSpec number will be followed by an MS for mud andsnow. See Tire Sidewall Labeling on page 5-49 foradditional information.GM recommends replacing tires in sets of four. This isbecause uniform tread depth on all tires will help keepyour vehicle performing most like it did when the tireswere new. Replacing less than a full set of tires can affectthe braking and handling performance of your vehicle.See Tire Inspection and Rotation on page 5-65 forinformation on proper tire rotation.{ CAUTION:Mixing tires could cause you to lose control ofyour vehicle while driving. If you mix tires ofdifferent sizes, brands, or types (radial andbias-belted tires), the vehicle may not handleproperly, and you could have a crash. Using tiresof different sizes, brands, or types may also causedamage to your vehicle. Be sure to use the correctsize, brand, and type of tires on all wheels.Your vehicle may have a compact spare tire andwheel assembly. If the vehicle has a compactspare tire and wheel, they have the same overalldiameter as your vehicle’s full-size tires andwheels. Because they were designed anddeveloped for use on your vehicle, it is all right todrive your vehicle with the compact spare installedproperly. Compact spare tires are designed fortemporary use only. See Spare Tire on page 5-85.5-68
