GMC Sierra Denali Owner's Manual page 284

When to Add Engine Oil
If the oil is at or below the cross-hatched area at the dip
of the dipstick, 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 engine oil crankcase capacity,
see Capacities and Specifications on page 5- 104.
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.
7 1
located on the passenger's
The engine oil fill cap is
side valve cover.
See Engine Comparfment Overview on page 5-12 for
more information on location.
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.
5-1 5