Oldsmobile 2003 Alero Owner's Manual page 232

When to Add Engine Oil
If the oil is at or below the MIN mark for the 2.2L L4
ECOTEC engine or below the cross-hatched area at the
tip of the dipstick for the 3400 V6 engine, 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 5-86
Notice: Don't add too much oil. If your engine has
so much oil that the oil level gets above the
upper mark that shows the proper operating range,
your engine could be damaged.
I
For the location of the
engine oil fill cap see
I A
SAE 5W-30
El
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.
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