1993 GMC Suburban Owner's Manual - Page 321

Standard No. 109. Grades B and A representhigherlevels ofperformanceon thelaboratorytestwheelthantheminimumrequired by law. Warning:Thetemperaturegradeforthis tire isestablishedforatirethat is properly inflated and not overloaded.Excessivespeed,underinflation, or excessiveloading,eitherseparatelyor in combination,cancauseheatbuildup andpossibletirefailure. Thosegradesaremolded on thesidewalls of passengercartires. WhilethetiresavailableasstandardoroptionalequipmentonGeneralMotors vehiclesmayvarywithrespect to thesegrades,allsuchtiresmeetGeneral Motorsperformancestandardsandhave been approvedforuseonGeneral Motorsvehicles. All passengertype (P Metric)tiresmustconformtoFederal safetyrequirements in additiontothesegrades. Wheel Alignment and Tire Balance Thewheelsonyourvehiclewerealignedandbalancedcarefullyatthe factory to giveyouthe longest tire life and bestoverallperformance. In mostcases,youwillnot need to haveyourwheelsalignedagain. However, if you noticeunusualtirewearoryourvehicle pulling onewayor theother,thealignmentmay need to bereset.Ifyounoticeyourvehicle vibratingwhendriving on asmoothroad,yourwheelsmayneedto be rebalanced. Whed Wepiacement Replaceanywheelthatisbent,crackedorbadlyrusted. If wheelnutskeep comingloose,thewheel,wheelbolts, and wheelnutsshouldbereplaced. If the wheelleaksairout,replace it (exceptsomealuminumwheels,whichcan if anyoftheseconditionsexist. Your be repaired).SeeyourGMtruckdealer dealerwillknowwhat kind ofwheelyouneed. Each new wheelshouldhavethesame load carryingcapacity,diameter, it replaces. width,offset,andbemountedthesamewayastheone If you need to replaceany of yourwheels,wheel bolts, orwheelnuts, replacethemonlywith new GM originalequipmentparts.This way, youwill be sureyouhavetherightwheel,wheelbolts,andwheelnutsforyour vehicle. 6-55