Geo 1995 Prizm Owner's Manual page 216

How to Check
Check to make sure that the fluid level is at the MIN
mark. If the level is below the MIN mark, see the
instructions on the reservoir cap.
Engine Coolant
The following explains your cooling system and how to add
coolant when it is low. If you have a problem with engine
overheating, see "Engine Overheating" in the Index.
The proper coolant for your Geo will:
0
Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 262°F (128 "C).
0
Protect against rust and corrosion.
Help keep the proper engine temperature.
0
Let the warning lights work as they should.
What to Use
Use
a
mixture of one-half clean water (preferably
distilled) and one-half antifreeze that meets "GM
Specification 1825M'" which won't damage aluminum
parts. You can also use a recycled coolant conforming to
GM Specification 1825M with a complete coolant flush
and refill. Use GM Engine Coolant Supplement (sealer)
with any complete coolant flush and refill. If you use
this mixture, you don't need to add anything else.
NOTICE:
If you use an improper coolant mix, your engine
could overheat and be badly damaged. The
repair cost wouldn't be covered by your
warranty. Too much water in the mix can freeze
and crack the engine, radiator, heater core and
other parts.
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