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4. Then fill 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.
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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 the filler neck until the level reaches
the base of the filler neck.
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to flow out of the
filler neck, reinstall the pressure cap.
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
If your vehicle has the DURAMAX Diesel engine, see
the DURAMAX Diesel manual for more information.
The vehicle has an indicator to warn of engine
overheating.
You will find an engine coolant temperature gage on
your vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 4-29for more information.You may decide not to lift the hood when this warning
appears, but instead get service help right away.
SeeRoadside Assistance Program on page 8-8.
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.
See if the engine cooling fan speed increases 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: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.
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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 drive
the 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 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 are parked. If you still have the warning,
turn off the engine until it cools down.
You may decide not to lift the hood but to get service
help right away.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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Your dealer/retailer 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 the wheels, wheel bolts,
wheel nuts or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM original
equipment parts. This way, you will be sure to have
the right wheel, wheel bolts, wheel nuts, and TPMS
sensors for the vehicle.
{WARNING:
Using the wrong replacement wheels, wheel bolts,
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control. You could have a collision in which
you or others could be injured. Always use the
correct wheel, wheel bolts, and wheel nuts for
replacement.Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance, and tire or tire chain
clearance to the body and chassis.
Whenever a wheel, wheel bolt or wheel nut is replaced
on a dual wheel setup, check the wheel nut torque after
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper torque, see “Wheel Nut Torque”
underCapacities and Speci cations on page 6-116.
SeeChanging a Flat Tire on page 6-86for more
information.
Used Replacement Wheels
{WARNING:
Putting a used wheel on the vehicle is dangerous.
You cannot know how it has been used or how
far it has been driven. It could fail suddenly and
cause a crash. If you have to replace a wheel,
use a new GM original equipment wheel.
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