GMC SAVANA 2004 Owner's Manual

Radiator Pressure CapThe radiator pressure cap is located near the center of
the engine compartment. SeeEngine Compartment
Overview on page 5-12for more information on location.
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
Engine Overheating
You will nd a coolant temperature gage on your
vehicle’s instrument panel.
5-25

If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood. Stay
away from the engine if you see or hear steam
coming from it. Just turn it off and get
CAUTION: (Continued)
CAUTION: (Continued)
everyone away from the vehicle until it cools
down. Wait until there is no sign of steam or
coolant before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
See “Overheated Engine Protection Operating
Mode” underEngine Overheating on page 5-25
for information on driving to a safe place in an
emergency.
Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty. See “Overheated
Engine Protection Operating Mode” underEngine
Overheating on page 5-25for information on driving
to a safe place in an emergency.
5-26

If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or hear
no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades” inTowing a
Trailer on page 4-37.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL(N)
while stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL(N) and let the
engine idle.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning doesn’t come back on, you can drive
normally.
If the warning continues, and you have not stopped, pull
over, stop, and park your vehicle right away.
If there’s still no sign of steam, push down the
accelerator until the engine speed is about twice as fast
as normal idle speed for at least three minutes while
you’re parked. If you still have the warning,turn off the
engine and get everyone out of the vehicleuntil it
cools down.
You may decide not to lift the hood but to get service
help right away.
5-27

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. Do not touch them. If
you do, you can be burned.
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine re, and you could be
burned. Get any leak xed before you drive the
vehicle.
5-28

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 is not 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:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
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 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.
5-29

Notice:Filling the engine cooling system of a V8
engine only through the radiator neck and engine
coolant overow reservoir after the engine coolant
has been drained may cause too little engine
coolant to be added. Although the coolant level may
appear full in the radiator neck, it may be as much
as 4 to 6 quarts (3.8 to 5.7 L) low. Always ll
the engine cooling system through the upper
radiator hose. See your dealer for more information.
{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. Do not spill coolant on a hot engine.
When the coolant in the coolant recovery tank is at the
COLD FILL mark, start your vehicle.
5-30

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.
{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.
5-31

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
it rst 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.2. Then keep turning the pressure cap, but now push
down as you turn it. Remove the pressure cap.
5-32

3. Fill the radiator with the proper DEX-COOL®
coolant mixture, up to the base of the ller
neck. SeeEngine Coolant on page 5-22for more
information about the proper coolant mixture.4. Then ll 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.
5-33

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
ller neck may be lower. If the level is lower, add
more of the proper DEX-COOL
®coolant mixture
through the ller neck until the level reaches
the base of the ller neck.8. Then replace the pressure cap. At any time during
this procedure if coolant begins to ow out of the
ller neck, reinstall the pressure cap.
5-34