2009 GMC ENVOY Owner's Manual

Checking Coolant
The vehicle must be on a level surface when checking
the coolant level.
Check to see if coolant is visible in the coolant recovery
tank. If the coolant inside the coolant recovery tank is
boiling, do not do anything else until it cools down.
If coolant is visible but the coolant level is not at
or above the FULL COLD mark, add a 50/50 mixture of
clean, drinkable water and DEX-COOL coolant at the
coolant recovery tank, but be sure the cooling system is
cool before this is done.
The coolant level should be at least up to the FULL
COLD mark. If it is not, there may be a leak in the
cooling system.
How to Add Coolant to the
Recovery Tank
{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.
Notice:This vehicle has a specic coolant ll
procedure. Failure to follow this procedure could
cause the engine to overheat and be severely
damaged.
If coolant is needed, add the proper DEX-COOL coolant
mixture at the coolant recovery tank.
When the coolant in the coolant recovery tank is at the
FULL COLD mark, start the vehicle.
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How to Add Coolant to the Radiator
{CAUTION:
An electric engine cooling fan under the hood 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.
{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 surge tank
pressure cap — even a little — they can come out
at high speed. Never turn the cap when the cooling
system, including the surge tank pressure cap, is
hot. Wait for the cooling system and surge tank
pressure cap to cool if you ever have to turn the
pressure cap.If coolant is needed, add the proper mixture directly to
the radiator, but be sure the cooling system is cool
before this is done.
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 about
one full turn. 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. Remove the
pressure cap.
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3. Fill the radiator with the proper DEX-COOL coolant
mixture, up to the base of the ller neck. See
Engine Coolant on page 5-25for more information
about the proper coolant mixture.4. Then ll the coolant recovery tank to the FULL
COLD mark.
5. Put the cap back on the coolant recovery tank,
but leave the radiator pressure cap off.
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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. Be sure
the pressure cap is hand-tight and fully seated.
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
The vehicle has several indicators to warn of engine
overheating.
You will nd a coolant temperature gage on the vehicle’s
instrument panel. SeeEngine Coolant Temperature
Gage on page 3-37for more information.
If the vehicle has a Driver Information Center (DIC), the
display will show an Engine Coolant Hot/Engine
Overheated message. SeeDIC Warnings and Messages
on page 3-51for more information.
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You may decide not to lift the hood when this warning
appears, but instead get service help right away.
SeeRoadside Assistance Program on page 7-7.
If you do decide to lift the hood, make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run
the engine and have the vehicle serviced.
Notice:Engine damage from running the engine
without coolant is not covered by the warranty.
Notice:If the engine catches re because of being
driven with no coolant, your vehicle can be badly
damaged. The costly repairs would not be covered
by the vehicle warranty.If Steam Is Coming From The Engine
Compartment
{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 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.
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If No Steam Is Coming From The
Engine Compartment
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
Climbs a long hill on a hot day.
Stops after high-speed driving.
Idles for long periods in traffic.
Tows a trailer.
If the overheat warning is displayed with no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and
to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral)
while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let
the engine idle.
If the temperature overheat gage is no longer in the
overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drivethe vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for three
minutes while parked. If the warning is still displayed,
turn off the engine until it cools down.Engine Fan Noise
The 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 clutch is not engaged. This improves fuel economy
and reduces fan noise. Under heavy vehicle loading,
trailer towing, and/or high outside temperatures, the fan
speed increases when the clutch 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 disengages.
You may also hear this fan noise when the engine is
started. The sound will go away as the fan clutch
disengages.
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Power Steering Fluid
SeeEngine Compartment
Overview on page 5-12for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check the power steering
uid unless you suspect there is a leak in the system
or you hear an unusual noise. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How to Check Power Steering Fluid
To check the power steering uid:
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. Remove the cap again and look at the uid level on
the dipstick.
For vehicles with the 4.2L L6 engine, the level
should be at the C (Cold) mark. For vehicles with the
5.3L V8 engine, the level should be at the FULL mark.
If necessary, add only enough uid to bring the level
up to the mark.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 6-12.
Always use the proper uid.
Notice:Use of the incorrect uid may damage the
vehicle and the damages may not be covered by the
vehicle’s warranty. Always use the correct uid listed
inRecommended Fluids and Lubricants on
page 6-12.
5-33

Windshield Washer Fluid
What to Use
When the vehicle needs windshield washer uid, be
sure to read the manufacturer’s instructions before use.
If the vehicle will be operating in an area where the
temperature may fall below freezing, use a uid that has
sufficient protection against freezing.
Adding Washer Fluid
Open the cap with the
washer symbol on it. Add
washer uid until the
tank is full. SeeEngine
Compartment Overview on
page 5-12for reservoir
location.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 the washer uid tank only three-quarters full
when it is very cold. This allows for uid
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 the vehicle’s
windshield washer system and paint.
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