1994 Buick Regal Owner's Manual - Page 218

What Kind of Oil to Use Beginning midyear 1993, oils of the proper quality for your vehicle will be identified with this new "starburst" symbol. The "starburst" symbol indicates that the oil has been certified by the American Petroleum Institute (API), and is preferred for use in your gasoline engine. You should look for this on the front of the oil container, and use only oils that display this new symbol. RECOMMENDED SA€ VISCOSITY GRADE ENGINE OILS FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST SAE VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE. w HOT WEATHER iOOK FOR ONE OF THESE LABELS You should also use the proper viscosity oil for your vehicle, as shown in the following chart: If your vehicle has the 3.8L engine, as shown in the chart, S A E 1OW-30 is best for your vehicle. However, you can use SAE 5W-30 if it's going to be colder than 60°F (16°C) before your next oil change. When it's very cold, you should use SAE 5W-30. These numbers on an oil container show its viscosity,or thickness. Do not use other viscosity oils, such as S A E 1OW-40 or S A E 2OW-50. COLD WEATHER 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 USE SAE 1W-40,SAE 2OW-50 OR ANY OTHER GRADE OIL NOT RECOMMENDED 216