Oldsmobile 1997 Aurora Owner's Manual page 236

A
CAUTION:
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@ coolant.
NOTICE:
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts. So
use the recommended coolant.
~~ ~
~
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Don't spill coolant on a hot engine.
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