1993 Buick Regal Owner's Manual - Page 223

A A r r A Don't add too muchoil. If your engine has so much oil that the oil level gets above the cross-hatched area that shows the proper range, operating your engine could be damaged. I il L L Just 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. L To Check Engine Oil: Pull out the dipstick and clean it with a paper towel or cloth, then push it back i n all the way. Remove it again, keeping the tip lower. When to Add Oil: If the oil is at or below the ADD line, then you'll need to add some oil. But you must use the right kind. This section explainswhat kind of oil to use. For crankcase capacity, see "Capacitiesand Specifications" in the Index. I I 221.