2004 CHEVROLET KODIAK cooling

Cooling System
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Engine Fan
B. Coolant Surge Tank
If your vehicle has a Caterpillar
®diesel engine, see the
Caterpillar®Diesel Engine Operation and Maintenance
Manual provided with your vehicle.
If the coolant inside the coolant surge tank is boiling,
don’t do anything else until it cools down. The vehicle
should be parked on a level surface.The coolant level should
be at COLD FILL or
higher. 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.
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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 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.
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.
How to Add Coolant to the Coolant
Surge Tank
If you haven’t found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level isn’t at COLD FILL or higher, add a
50/50 mixture ofclean, drinkable waterand DEX-COOL
®
coolant at the coolant surge tank, but be sure the
cooling system, including the coolant surge tank
pressure cap, is cool before you do it. SeeEngine
Coolant (Gas and DURAMAX™ engines) on page 5-32
orEngine Coolant (Caterpillar
®Diesel Engines) on
page 5-35for more information.
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If no coolant is visible in the surge tank, add coolant as
follows:
{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 coolant
surge tank pressure cap — even a little — they
can come out at high speed. Never turn the
cap when the cooling system, including the
coolant surge tank pressure cap, is hot. Wait
for the cooling system and coolant surge tank
pressure cap to cool if you ever have to turn
the pressure cap.
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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: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.
1. Park the vehicle on a level surface. You can
remove the coolant surge tank pressure cap
when the cooling system, including the coolant
surge tank pressure cap and upper radiator hose, is
no longer hot. Turn the pressure cap slowly
counterclockwise (left) 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 slowly, and
remove it.
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3. Then fill the coolant surge tank with the proper
mixture, to the FULL mark.4. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower,
add more of the proper mixture to the coolant
surge tank until the level reaches slightly above the
FULL mark.
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5. Then replace the
pressure cap. Be sure
the pressure cap is
hand-tight and
fully seated.
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 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 when the clutch
engages. So you may hear an increase in fan noise.
This is normal and should not be mistaken as thetransmission 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
See your Maintenance Schedule for when to check your
power steering fluid.
How To Check Power Steering Fluid
Check your power steering fluid only when the engine is
warm. If the engine isn’t warm, you probably won’t
get an accurate reading.
If the fluid level is between the MIN and MAX marks,
you have enough. If you need fluid, add only enough of
the proper fluid to bring it in between the MIN and
MAX marks.
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6. Install a new gasket whenever you take out the
cylinder. Use only one gasket and spread a light
film of clean oil on it before installation.
7. Put in the new cylinder. Turn it clockwise until it just
starts to contact the gasket.
8. Tighten the cylinder another half turn (180 degrees).
Don’t over-tighten.
9. Retighten the cylinder clamp.
Front Wheel Bearings with
Oil-Filled Hubs
If your vehicle has oil-filled
hubs, occasionally check
to see if they have enough
oil. You can tell if there
is oil there by using
the circular gage on the
sight glass.If there isn’t, clean the rubber fill plug in the center of
the glass, and then remove it. Be careful not to
allow any dirt or water to get into the oil. Add enough of
the recommended oil to bring it up to the level mark
that you’ll see on the glass.
Refer to your Maintenance Schedule for the proper oil
to use.
When you fill the hub, check the glass again after
driving a short distance. It takes a while for the oil to
flow through the system, and you may find that you have
to add a little more to fill it to the proper level. Be sure
not to overfill the hub.Air Conditioning System
Every now and then, have your dealership check your
air conditioning system to be sure it has not lost
any cooling ability. If you think the system is not working
properly, have your GM dealer check it out as soon
as possible.
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Wheel Replacement
Replace any wheel that is bent, cracked or badly rusted
or corroded. If wheel nuts keep coming loose, replace
the wheel. If the wheel leaks air, replace it.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle.
{CAUTION:
A leaking wheel could fail without warning.
A wheel designed for tubeless tires could be
leaking because it is damaged. Don’t use
an inner tube or some other thing to try to
stop the leaking. Get a new wheel or the
proper type.
{CAUTION:
Without the correct wheel, you may not be able
to stop properly, and you could have other
problems like a tire air-out. You could have a
collision. If you don’t go to your dealer to get a
new wheel, be sure you get the correct one.
Each new wheel should match the original
wheel in load-carrying capacity, ination
pressure capacity, diameter, width, offset and
mounting conguration.
Using wheels and tires with higher load-carrying limits
than the original wheels and tires doesn’t change
the GAWR or the GVWR of your vehicle. See “Loading
Your Vehicle” for more information.
Notice:The wrong wheel can cause trouble in
bearing life, brake cooling, speedometer/odometer
calibration, headlamp aim, bumper height, vehicle
ground clearance, stopping distance and tire
clearance to the body and chassis. You could also
have other problems like a tire air-out.
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