2008 CHEVROLET COLORADO Owners Manual

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” under
Towing a Trailer on page 4-48.
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
while stopped. If it is safe to do so, pull off the
road, shift to P (PARK) or NEUTRAL and let the
engine idle.
2. Turn off the air conditioning.
3. Turn on your heater to full hot at the highest fan
speed and open the windows 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 does not come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there is still no sign of steam, idle the engine for
three minutes while you are parked. Push down the
accelerator until the engine speed is about twice as fast
as normal idle speed for at least three minutes while you
are parked. If you still have the warning, turn off the
engine and get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get service
help right away.
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Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Recovery Tank
B. Engine Cooling Fan
C. Radiator Pressure Cap
If the coolant inside the coolant recovery tank is boiling,
do not do anything else until it cools down. The
vehicle should be parked on a level surface.When the engine is cold, the coolant level should be at
least up to the FULL COLD mark. If it is not, 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.
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{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.
If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
down. If it does not, your vehicle needs service. Turn off
the engine.Notice:Engine damage from running the engine
without coolant is not covered by the warranty.
Notice:Using coolant other than DEX-COOL
®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL
®(silicate-free) coolant in the
vehicle.
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How to Add Coolant to the Coolant
Recovery Tank
If you have not found a problem yet, but the
coolant level is not at the FULL COLD mark, add a
50/50 mixture of clean, drinkable water and
DEX-COOL
®engine coolant at the coolant recovery
tank. SeeEngine Coolant on page 5-27for more
information.
{CAUTION:
Adding only plain water to the cooling system
can be dangerous. Plain water, or some other
liquid such as alcohol, can boil before the
proper coolant mixture will. The vehicle’s
coolant warning system is set for the proper
coolant mixture. With plain water or the wrong
mixture, the engine could get too hot but you
would not get the overheat warning. The
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: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.
{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
FULL COLD mark, start your vehicle.
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If the overheat warning continues, there is one more
thing you can try. Add the proper 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
1. Remove the radiator pressure cap when the cooling
system, including the 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. Keep turning the cap to remove it.
3. Fill the radiator with the proper DEX-COOL
®
coolant mixture, up to the base of the ller
neck. SeeEngine Coolant on page 5-27for more
information about the proper coolant mixture.
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4. Fill the coolant recovery tank to the FULL
COLD mark.
5. Reinstall the cap 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
ller neck might 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 to secure it tightly.
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Engine Fan Noise
This 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 you start the
engine. It will go away as the fan clutch disengages.
Power Steering Fluid
The power steering uid
reservoir is located near
the front of the engine
compartment, behind the
radiator. SeeEngine
Compartment Overview on
page 5-12for reservoir
location.
When to Check Power Steering Fluid
It is not necessary to regularly check 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.
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How to Check Power Steering Fluid
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 uid
level on the dipstick.
The level should be between the ADD and FULL marks.
If necessary, add only enough uid to bring the level
up to the proper range.
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 your
vehicle and the damages may not be covered by
your warranty. Always use the correct uid listed in
Recommended Fluids and Lubricants on page 6-12.
Windshield Washer Fluid
What to Use
When you need windshield washer uid, 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 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.
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