Cadillac 2011 STS Owner's Manual page 367

If the oil is below the cross-hatched area at the tip of
the dipstick, add one liter/quart of the recommended oil
and then recheck the level. See Selecting the Right
Engine Oil for an explanation of what kind of oil to use.
For engine oil crankcase capacity, see
.
See
the location of the engine oil fill cap.
Add enough oil to put the level somewhere in the proper
operating range. Push the dipstick all the way back in
when through.
for
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