GMC SIERRA DENALI 2002 Manual page 257

CAUTION: (Continued)
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 mixture of clean, drinkable water
R
-
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.
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. Don't spill coolant on a hot engine.
1. Park the vehicle on a
Turn the pressure cap slowly counterclockwise (left)
about one full turn. If you hear a hiss, wait for that to
stop. A hiss means there is still some pressure left.
level surface. You can
remove the coolant
surge tank pressure cap
when the cooling
system, including the
coolant surge tank
pressure cap and upper
radiator hose, is no
longer hot.
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