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{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.
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 re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:
When using concentrated washer uid,
follow the manufacturer’s instructions
for adding water.
Do not mix water with ready-to-use washer
uid. Water can cause the solution to
freeze and damage your washer uid tank
and other parts of the washer system.
Also, water does not clean as well
as washer uid.
Fill your washer uid tank only
three-quarters full when it is very cold.
This allows for expansion if freezing
occurs, which could damage the tank if it
is completely full.
Do not use engine coolant (antifreeze) in
your windshield washer. It can damage
your washer system and paint.
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.
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{CAUTION:
You can be burned if you spill coolant
on hot components in the engine
compartment. Coolant contains ethylene
glycol, and it will burn if the engine parts
are hot enough. Do not spill coolant on a
hot engine or components in the engine
compartment.
When the coolant in the coolant recovery tank is
at the COLD FILL mark, start your vehicle.
If the overheat warning continues, there is
one more thing you can try. You can add the
proper coolant mixture directly to the radiator,
but be sure the cooling system is cool before
you do it.
{CAUTION:
Steam and scalding liquids from a hot
cooling system can blow out and burn you
badly. They are under pressure, and if you
turn the radiator pressure cap — even a
little — they can come out at high speed.
Never turn the cap when the cooling
system, including the radiator pressure
cap, is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever
have to turn the pressure cap.
How to Add Coolant to the Radiator for
Gasoline Engines
If your vehicle has a diesel engine, see “How to
Add Coolant to the Radiator” under “Van Models”
in the Cooling System section of the DURAMAX
®
Diesel Supplement for the proper radiator fill
procedure.
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1. You can remove the radiator pressure cap
when the cooling system, including the radiator
pressure cap and upper radiator hose, is no
longer hot. Turn the pressure cap slowly
counterclockwise until it first stops. Do not
press down while turning the pressure cap.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
2. Then keep turning the pressure cap, but now
push down as you turn it. Remove the
pressure cap.3. Fill the radiator with the proper DEX-COOL®
coolant mixture, up to the base of the filler
neck. SeeEngine Coolant on page 306for
more information about the proper coolant
mixture.
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4. Then fill the coolant recovery tank to the
COLD FILL mark.
5. Put the cap back on the coolant recovery tank,
but leave the radiator pressure cap off.6. Start the engine and let it run until you can
feel the upper radiator hose getting hot.
Watch out for the engine cooling fan.
7. By this time, the coolant level inside the
radiator filler neck may be lower. If the level is
lower, add more of the proper DEX-COOL
®
coolant mixture through the filler neck until the
level reaches the base of the filler neck.
8. Then replace the pressure cap. At any time
during this procedure if coolant begins to flow
out of the filler neck, reinstall the pressure cap.
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