GMC 2003 Safari Owner's Manual page 233

When to Add Engine Oil
If the oil is at or below the ADD line, 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 5-99.
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.
The engine oil fill cap is located on the valve cover in
the engine compartment on the passenger's side of the
vehicle. Your vehicle may have a cap with text and a
graphic
or
just a graphic as shown above. See Engine
Compartment Overview on page 5-14 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.
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