If You Are Asking What Brand, That Is Up To You. The Viscosity Weight, A Good 10 W 40, Would Be Just Fine For The Engine.
where is located the oil pressure switch for 94 geo prizm
I would recommend 5w-30
The oil capacity on a 1996 Geo Prizm is approximately 5 quarts. The recommended oil type is 10 W 30.
5W30
Every 5.000 miles
4 quarts
May have to change oil.
http://www.ehow.com/video_11_change-motor-oil.html this helped me HUGE!!!
1.6 liter holds three quarts with a filter change.
75-90 weight gear oil
chances are you need a new head gasket, or some other seal
It is generally 10W-30 but can depend on your ambient temperature. At colder temperatures you need thinner oil. You should be able to find this information in your owner's manual and it is also stamped on the oil filler cap if it is the original.