Chevrolet 1997 Malibu Owner's Manual page 240

A 50/50 mixture of water and the proper coolant for
your Chevrolet will:
Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265
O F
(129
O
C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let
the warning lights and gages work as they should.
NOTICE:
When adding coolant, it is important that you use
only DEX-COOL
TM
(silicate-free) coolant.
If silicated coolant is added to the system,
premature engine, heater core or radiator
corrosion may result. In addition, the engine
coolant will require change sooner
--
at
30,000 miles (50 000 km) or 24 months,
whichever occurs first.
What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half DEX-COOL
TM
coolant which
won't damage aluminum parts. If you use this mixture,
you don't need to add anything else.
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mix will. Your vehicle's coolant warning
system is set for the proper coolant mix. With
plain water or the wrong mix, your engine could
get too hot but you wouldn't get the overheat
warning. Your engine could catch fire and you or
others could be burned. Use a 50/50 mix of clean
water and DEX-COOL
TM
coolant.
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