1993 Buick Regal Owner's Manual - Page 225

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. 0 If you have the 3.1L engine use: SAE 5W-30 As shown in the viscosity chart, SAE 5W-30 is best for your vehicle. However, you can use SAE 1OW-30 if it's going tobe O°F (-18OC) or above. These numbers on an oil container show its viscosity, or thickness. Do not use other viscosity oils such as SAE low-40 or SAE 20W-50. HOT WEATHER I "F r k100 - - +38 +80 - - +27 +16 +60 +40 -. - - +4 - -18 +20 - - -7 0- -- 5W-30 SA -SAE 1 PREFERRED COLD WEATHER I' 0 Energy Conserving I1 Oils with these words on the container will help you save fuel. This doughnut-shaped logo (symbol) used on most oil is containers to helpyou select thecorrect oil. You should look for this on the oil container, and use only those oils that display the logo. oil GM Goodwrench@ (in Canada, GM Engine Oil) meets all the requirements for your vehicle. Engine Oil Additives: Don't add anything to your oil. IF NEITHER SAE 5W-30 NOR SAE 1OW-30 GRADE OILS ARE AVAILABLE, SAE 30 GRADE MAY BE USED AT TEMPERATURES ABOVE 40 DEGREES F (4 DEGREES C). DO NOT USESAE 1OW-40, SAE 2OW-50 OR ANY OTHER GRADE OIL NOT RECOMMENDED Your Buick dealer is ready to advise if you think something should be added. 223