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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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Engine Fan Noise
Your vehicle has a clutched engine cooling fan.
When the clutch is engaged, the fan spins faster to
provide more air to cool the engine. In most
everyday driving conditions, the fan is spinning
slower and the clutch is not fully engaged.
This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing,
and/or high outside temperatures, the fan speed
increases as the clutch more fully engages, so you
may hear an increase in fan noise. This is
normal and should not be mistaken as the
transmission slipping or making extra shifts. It is
merely the cooling system functioning properly.
The fan will slow down when additional cooling is
not required and the clutch partially disengages.
You may also hear this fan noise when you
start the engine. It will go away as the fan clutch
partially disengages.
Power Steering Fluid
The power steering fluid
reservoir is located in
the engine compartment
on the driver’s side of
the vehicle. SeeEngine
Compartment Overview
on page 296for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering fluid unless you suspect there is a leak in
the system or you hear an unusual noise. A
fluid loss in this system could indicate a problem.
Have the system inspected and repaired.
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How to Check Power Steering Fluid
To check the power steering fluid, do the following:
1. Turn the key off and let the engine
compartment cool down.
2. Wipe the cap and the top of the
reservoir clean.
3. Unscrew the cap and wipe the dipstick with a
clean rag.
4. Replace the cap and completely tighten it.
5. Then remove the cap again and look at
the fluid level on the dipstick.
The level should be at the COLD FILL mark. If
necessary, add only enough fluid to bring the level
up to the mark.
To prevent contamination of brake fluid, never
check or fill the power steering reservoir with the
brake master cylinder cover off.
What to Use
To determine what kind of fluid to use, see
Recommended Fluids and Lubricants on page 409.
Always use the proper fluid. Failure to use the
proper fluid can cause leaks and damage hoses
and seals.
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to
read the manufacturer’s instructions before use. If
you will be operating your vehicle in an area where
the temperature may fall below freezing, use a fluid
that has sufficient protection against freezing.
Adding Washer Fluid
Open the cap with the
washer symbol on it.
Add washer fluid
until the tank is full. See
Engine Compartment
Overview on page 296
for reservoir location.
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