Cadillac 2004 XLR - Manual (Page 253)

{ CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will.
CAUTION: (Continued)
CAUTION: (Continued)
Your vehicle’s coolant warning system is set
for the proper coolant mixture. With plain
water or the wrong mixture, your engine could
get too hot but you would not get the overheat
warning. Your engine could catch fire and you
or others could be burned. Use a 50/50 mixture
of clean, drinkable water and DEX-COOL
®
coolant.
Notice: In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{ CAUTION:
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. Do not spill coolant on a hot engine.
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