Geo 1995 Prizm Owner's Manual page 209

As shown in the chart, SAE 1OW-30 is best for your
vehicle. However, you can use S A E 5W-30 if it's
going to be colder than 60°F (1 6
O
C)
before your
next oil change. When it's very cold, you should use
SAE 5W-30. These numbers on an oil container show
its viscosity, or thickness. Do not use other viscosity
oils, such as SAE 20W-50.
I
NOTICE:
I
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
"Starburst" symbol. Failure to use the proper oil
can result in engine damage not covered by your
warranty.
GM Goodwrench@ oil (in Canada, GM Engine Oil)
meets all the requirements
for
your vehicle.
Engine Oil Additives
Don't add anything to your oil. Your ChevroletYGeo
dealer is ready to advise
if
you think something should
be added.
When to Change Engine Oil
See if any one of these is true for you:
Most trips are less than 5 to 10 miles (8 to 16
km).
This
is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such as frequent
driving in stop and go traffic).
Most trips are through dusty areas.
You frequently tow a trailer or use a carrier on top of-
If any one of these is true for your vehicle, then you
need to change your oil and filter every 3,000 miles
(5 000
km)
or 3 months
--
whichever comes first.
If none of them is true, change oil and filter every
7,500 miles (12 500 k m ) or 12 months
--
whichever
comes first.
your vehicle.