1993 GMC Safari Owner's Manual - Page 242

Service & Appearance Care NOTICE If youtry to do your service own wo your vehiclecouldbe damag . withoutknowingenoughabout it, 1 Fuel K3650 The8thdigit ofyourVehicle IdentificationNumber(VIN)showsthecode letter for your engine. You will find the VIN at the top left of your instrument panel.(See"VehicleIdentificationNumber" in the Index.) Useregularunleadedgasolineratedat87octaneorhigher.Withthe4.3L (CodeW)engine,usepremiumunleaded gasolineratedat 91octaneor higher for highpowerperformance,whentowingatrailerorwithahigh payloadrequirement.Butwhenoperatingwithalightloadasanormal condition,youmayusemiddlegrade or regularunleadedgasolines. ASTM D4814 in the U.S. Thegasolineyouuseshouldmeetspecifications and CGSB 3.5-92 in Canada.Thesefuelsshouldhavetheproperadditives, so youshould nothave to addanything to thefuel. In the US. andCanada,it'seasy to besureyougettheright kind of gasoline(unleaded).You'llsee UNLEADED rightonthepump.Andonly unleaded nozzles will fit into your vehicle's filler neck. Besurethepostedoctane is atleast91forpremium,89formiddlegrade and 87 forregular. If theoctane is lessthan87,youmaygetaheavy If it'sbadenough, it candamageyour knockingnoisewhenyoudrive. engine. 6-4