2003 Chevrolet Monte Carlo Owner's Manual - Page 253

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. If you choose to perform the engine oil change service yourself, be sure the oil you use has the starburst symbol on the front of the oil container. If you have your oil changed for you, be sure the oil put into your engine is American Petroleum Institute certified for gasoline engines. RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS HOT WEATHER "C + 38 + 100 - t 80 + 27 + 60 +40 t 20 ~ + 16 +4 . -1 - 18 I 0- You should also use the proper viscosity oil for your vehicle, as shown in the viscosity chart. 1 AVAllABLE -30 RECOMMENDED ~1 ~ . i ~ LOOK FOR MIS SYMBOL 1 1 - 1 ACCEPTABLE 1OW-30 SAE IF 5W-30IS NOT CI LD WEATHER DO NOT USE SAE1OW-40, SAE 2OW-50 OR ANY OTHER VISCOSITY GRADEOIL NOT RECOMMENDED 3400 (Code E) V6 Engine 5-18