1998 Oldsmobile 88 Owner's Manual - Page 241
1998 Oldsmobile 88 Manual
Page 241 highlights
Checking Engine Oil Pull out the dipstick and clean it with a paper towel or cloth, then pushit back in all the way. Removeit again, keeping the tip down, and check level. the 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 oil. But you must use the of of right kind. Thispart explains what kind oil to use.For crankcase capacity, see "Capacities and Specifications" in the Index. I NOTICE: Don't add too much If your engine has oil. so much oil that the oil level gets above the cross-hatched area that shows the proper operating range, your engine could be damagea. The engineoil fill cap is behindthe engine oil dipstick and enginefans. Be sure to it enough to putthe level somewherein fill the proper operating range. Push dipstick all the way the back in when you're through. 6-12