292 VEHICLE CAREageing. This area should be free ofgrease, petrol, or other substancesthat can deteriorate rubber.Parking for an extended period cancause flat spots on the tyres that mayresult in vibrations while driving.When storing a vehicle for at least amonth, remove the tyres or raise thevehicle to reduce the weight from thetyres.Buying New TyresGM has developed and matchedspecific tyres for the vehicle. Theoriginal equipment tyres installedwere designed to meet GeneralMotors Tyre Performance CriteriaSpecification (TPC Spec) systemrating. When replacement tyresare needed, GM stronglyrecommends buying tyres with thesame TPC Spec rating.GM's exclusive TPC Spec systemconsiders over a dozen criticalspecifications that impact theoverall performance of the vehicle,including brake systemperformance, ride and handling,traction control, and tyre pressuremonitoring performance. GM'sTPC Spec number is moulded ontothe tyre's sidewall near the tyresize. If the tyres have anall-season tread design, the TPCSpec number will be followed byMS for mud and snow.GM recommends replacing worntyres in complete sets of four.Uniform tread depth on all tyreswill help to maintain theperformance of the vehicle.Braking and handling performancemay be adversely affected if all thetyres are not replaced at the sametime. If proper rotation andmaintenance have been done, allfour tyres should wear out atabout the same time. See TyreRotation 0 290 for information onproper tyre rotation. However, if itis necessary to replace only oneaxle set of worn tyres, place thenew tyres on the rear axle.{ WarningTyres could explode duringimproper service. Attempting tomount or dismount a tyre couldcause injury or death. Only yourdealer or authorised tyre servicecentre should mount ordismount the tyres.Winter tyres with the same speedrating as the original equipmenttyres may not be available for H,V, W, Y and ZR speed rated tyres.Never exceed the winter tyre'smaximum speed capability whenusing winter tyres with a lowerspeed rating.{ WarningNever drive faster than the speedthe tyres are rated, regardless of thelegal speed limit. When frequentlydriving the vehicle at high speeds(Continued)
