2003 GMC Safari Owner's Manual - Page 234

What Kind of Engine Oil to Use Oils recommended for your vehicle can be identified by looking for the starburst symbol. This symbol indicates that the oil has been certified by the American Petroleum Institute (API). Do not use any oil which does not carry this starburst symbol. RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS HOT WEATHER I I If youchoose to perform the engine oil change service yourself, be sure the oil you use hasthe starburst symbol onthe front of the oil container. If you have your oil sure changed for you, be the oil put into your engine is American Petroleum Institute certified for gasoline engines. "F 100 - LOOK FOR THIS SYMBOL 7 "C + 38 + t 80 - + 27 + 16 t4 60 - + 40 t 20 0- -7 18 m IUW-30 PTABLE 30 IS NOT IlABLE RECOMMENDED You should also use the proper viscosity oil for your vehicle, as shown in the viscosity chart. WEATHER DO NOT USESAE 1OW-40, SAE 2OW-50 OR ANY OTHER VISCOSITY GRADEOIL NOT RECOMMENDED 5-17