1996 Buick LeSabre Owner's Manual - Page 241

As shown in the chart, SAE low-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. Donot use other viscosity oils, such as SAE 20W-50. When to Change Engine Oil See if any one of these is true for you: Most trips are less than 5 to 10 miles (8 to 16 km). This is particularly importantwhen outside temperatures arebelow freezing. Most trips include extensive idling (such as frequent driving in stop-and-go traffic). 0 I NOTICE: Use only engine oil with the American Petroleum Institute Certified For Gasoline Engines "Starburst" symbol. Failure to use the recommended oil can result in engine damage not covered by your warranty. GM Goodwrench' oil meets all the requirements for your vehicle. Most trips are through dusty areas. You frequently tow a trailer or use a carrier on top of your vehicle. 0 The vehicle is used for delivery service, police, taxi or othercommercial application. Driving under these conditions causes engine to oil break down sooner. If any one of these is true for your vehicle, then you need to change your oil and filter every 3,000 miles (5 000 km) or 3 months -- whichever occurs first. (See "Change Oil Indicator'' in the Index.) If none of them is true, change the oil and filter every 7,500 miles (12 500 km) or 12 months -- whichever occurs first.Driving a vehicle with a fully warmed engine under highway conditions causes engine to oil break down slower. (See "Change Oil Indicator'' in the Index.) Engine Oil Additives Don't add anything to your oil. Your Buick dealer is ready to advise if you think something should be added. 6-13