Chevrolet 2003 Silverado 1500 Pickup Owner's Manual page 394

When to Add Engine Oil
If the oil is at or below the cross-hatched area at the tip
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- 120.
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 for
the VORTEC 4800,5300
and 6000 V8 engines is
located on the engine valve
cover on the passenger's
side of the vehicle. On the
81 00 engine, the oil fill cap
is located on the front of
the engine. See Engine
Compartment 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.
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