1999 Buick LeSabre Owner's Manual - Page 248
1999 Buick LeSabre Manual
Page 248 highlights
yellowblue Checking Engine Oil Pull out the dipstick and clean it with a paper towel or cloth, then push it back in all the way. Remove it again, keeping the tip down, and check the level. NOTICE: Don't add too much oil. If your engine has so much oil that the oil level gets above the cross-hatched area that shows the proper operating range, your engine could be damaged. The engine oil fill cap is behind the engine oil dipstick and engine fans. Be sure to fill it enough to put the level somewhere in the proper operating range. Push the dipstick all the way back in when you're through. When to Add Engine Oil If the oil is at or below the ADD mark, then you'll need to add at least one quart of oil. But you must use the right kind. This part explains what kind of oil to use. For crankcase capacity, see "Capacities and Specifications" in the Index. 6-12