2003 GMC SAVANA cooling

Notice:When adding coolant, it is important that
you use only DEX-COOL®(silicate-free) coolant.
If coolant other than DEX-COOL®is added to the
system, premature engine, heater core or radiator
corrosion may result. In addition, the engine coolant
will require change sooner -- at 30,000 miles
(50,000 km) or 24 months, whichever occursfirst.
Damage caused by the use of coolant other than
DEX-COOL
®is not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOL®coolant which won’t damage
aluminum parts. If you use this coolant mixture,
you don’t need to add anything else.
{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)
You 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 wouldn’t get the overheat warning.
Your engine could catchfire and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and the proper coolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you don’t
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
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Add coolant mixture at the recovery tank, but be careful
not to spill it.
{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.
Occasionally check the coolant level in the radiator.
For information on how to add coolant to the radiator,
seeCooling System on page 5-28.
Radiator Pressure Cap
The radiator pressure cap is located near the center of
the engine compartment.
Notice:Your radiator cap is a pressure-type cap
and must be tightly installed to prevent coolant loss
and possible engine damage from overheating.
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Cooling System
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Radiator Pressure Cap
B. Coolant Recovery Tank
C. Engine Cooling Fan(s)
If the coolant inside the coolant recovery tank is boiling,
don’t do anything else until it cools down.When the engine is cold,
the coolant level should be
at or above the COLD
FILL mark. If it isn’t, you
may have a leak at
the pressure cap or in the
radiator hoses, heater
hoses, radiator, water
pump or somewhere else
in the cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Don’t touch them.
If you do, you can be burned.
Don’t run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an enginefire, and you could be
burned. Get any leakfixed before you drive
the vehicle.
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If there seems to be no leak, start the engine again.
See if the engine cooling fan speed increases when idle
speed is doubled by pushing the accelerator pedal
down. If it doesn’t, your vehicle needs service. Turn off
the engine.
Notice:Engine damage from running your engine
without coolant isn’t covered by your warranty.
See“Overheated Engine Protection Operating
Mode”in the Index for information on driving to
a safe place in an emergency.
Notice:When adding coolant, it is important that
you use only DEX-COOL
®(silicate-free) coolant.
If coolant other than DEX-COOL®is added to the
system, premature engine, heater core or radiator
corrosion may result. In addition, the engine coolant
will require change sooner—at 30,000 miles
(50 000 km) or 24 months, whichever occursfirst.
Damage caused by the use of coolant other than
DEX-COOL
®is not covered by your new vehicle
warranty.
If there seems to be no leak, start the engine again.
See if the engine cooling fan speed increases when
idle speed is doubled by pushing the accelerator
pedal down. If it doesn’t, your vehicle needs service.
Turn off the engine.
How to Add Coolant to the Coolant
Recovery Tank
If you haven’t found a problem yet, but the coolant level
isn’t at the COLD FILL mark, add a 50/50 mixture of
clean, drinkable waterand DEX-COOL
®engine coolant
at the coolant recovery tank. SeeEngine Coolant on
page 5-22for more information.
{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 wouldn’t get the overheat warning.
Your engine could catchfire 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.
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2003 - Savana OM

{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.When the coolant in the coolant recovery tank is at the
COLD FILL mark, start your vehicle.
If the overheat warning continues, there’s 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.
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2003 - Savana OM

{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
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
itfirst stops. (Don’t 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.
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2003 - Savana OM

4. Thenfill 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 thefiller neck until the level reaches
the base of thefiller neck.
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8. Then replace the pressure cap. At any time during
this procedure if coolant begins toflow out of the
filler neck, reinstall the pressure cap.
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.
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