Pontiac 1996 Grand Am Owner's Manual page 235

What Kind of'Oil to Use
3.1L Engine
The 3.1L engine oil fill cap is on the front of the engine,
behind the radiator.
Just 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.
Oils
recommended
for your vehicle can be
identified by
looking for the "Starburst" symbol. This symbol
indicates that the oil has been certified by the American
Petroleum Institute
(API). Do
not use any oil which
does not carry this Starburst symbol.
If you change your own oil,
be sure you use oil that has
the Starburst symbol on the
front of the oil container. If
you have your oil changed
for you, be sure the oil put
into your engine is
American Petroleum
Institute certified for
gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the following chart:
6-13