1998 Oldsmobile 88 Owner's Manual - Page 242

What Kind of Engine Oilto Use Oils recommendedfor your vehiclecan be identified by looking for the "Starburst" symbol. This symbol indicates that the has been certified by the American oil Petroleum Institute (API). Do not use anyoil which does not carry this Starburst svmbol. RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST SAE VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE. If you change your own oil, be sure you use oil that hasthe 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. You should alsouse the proper viscosityoil for your vehicle, as shown the following chart: in HOT WEATHER r 7 WOK FOR MIS SYMBOL "F t 100- +80- +60 +40- + 20 0- I 4 COLD WEATHER I + 38 + 27 + 16 +4 "C -7 - 18 SAE sw-30 DO NOT USE SAE 2OW-50 OR ANY OTHER GRADE OIL NOT RECOMMENDED 6-13