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Chevrolet/GMC 3.0L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-13336148) - 2020 - CRC - 9/5/19
Vehicle Care
43
{
Warning
An underhood electric fan can
start up even when the engine is
not running and can cause injury.
Keep hands, clothing, and tools
away from any underhood
electric fan.
{
Warning
Do not touch heater or radiator
hoses, or other engine parts.
They can be very hot and can
burn you. Do not run the engine if
there is a leak; all coolant could
leak out. That could cause an
engine fire and can burn you. Fix
any leak before driving the
vehicle.
Engine Coolant
The cooling system in the vehicle is
filled with DEX-COOL engine
coolant mixture. See
and
The following explains the cooling
system and how to add coolant
when it is low. If there is a problem
with engine overheating, see
.
A 50/50 mixture of clean, drinkable
water and DEX-COOL coolant will:
.
Give freezing protection down to
−
37 °C (
−
34 °F).
.
Give boiling protection up to
129 °C (265 °F).
.
Protect against rust and
corrosion.
.
Help keep the proper engine
temperature.
.
Let the warning lights and
gauges work as they should.
What to Use
{
Warning
Plain water, or other liquids such
as alcohol, can boil before the
proper coolant mixture will. With
plain water or the wrong mixture,
the engine could get too hot but
there would not be an overheat
warning. The engine could catch
fire and you or others could be
burned.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant which will not damage
aluminum parts. If using this
mixture, nothing else needs to be
added.
If coolant has to be added more
than four times a year, have your
dealer check the vehicle cooling
system.