cooling CHEVROLET EXPRESS CARGO VAN 2007 1.G User Guide

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, and you have not
stopped, pull over, stop, and park your 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 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.
Cooling System
If your vehicle has a diesel engine, see
“Van Models” under “Cooling System” in
the DURAMAX
®Diesel Supplement.When you decide it is safe to lift the hood, here is
what you will see:
A. Radiator Pressure Cap
B. Coolant Recovery Tank
C. Engine Cooling Fan(s)
If the coolant inside the coolant recovery tank is
boiling, do not do anything else until it cools down.
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When the engine is cold, the coolant level should
be at or above the COLD FILL 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.
{CAUTION:
Heater, fuel operated heater (FOH),
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. 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 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 could 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
Recovery Tank for Gasoline Engines
If your vehicle has a diesel engine, see
“How to Add Coolant to the Coolant Recovery
Tank” under “Van Models” in the Cooling System
section of the DURAMAX
®Diesel Supplement
for the proper coolant fill procedure.
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If you have not found a problem yet, but the
coolant level is not at the COLD FILL mark,
add a 50/50 mixture of clean, drinkable water
and DEX-COOL
®engine coolant at the coolant
recovery tank. SeeEngine Coolant on page 312
for 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.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.
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.
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{CAUTION:
You can be burned if you spill coolant
on hot components in the engine
compartment. Coolant contains ethylene
glycol, and it will burn if the engine parts
are hot enough. Do not spill coolant on a
hot engine or components in the engine
compartment.
When the coolant in the coolant recovery tank
is at the COLD FILL mark, start your vehicle.
If the overheat warning continues, there is
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.
How to Add Coolant to the Radiator
for Gasoline Engines
If your vehicle has a diesel engine, see
“How to Add Coolant to the Radiator” under
“Van Models” in the Cooling System section
of the DURAMAX
®Diesel Supplement for the
proper radiator fill procedure.
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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 first stops. Do not
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.3. Fill the radiator with the proper DEX-COOL®
coolant mixture, up to the base of the filler
neck. SeeEngine Coolant on page 312
for more information about the proper
coolant mixture.
321

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.
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.
322

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.
Power Steering Fluid
The power steering fluid
reservoir is located in
the engine compartment
on the driver’s side of
the vehicle. SeeEngine
Compartment Overview
on page 302for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering fluid unless you suspect there is a leak
in the system or you hear an unusual noise.
A fluid loss in this system could indicate a problem.
Have the system inspected and repaired.
323

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:
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 Specications on page 398.
SeeChanging a Flat Tire on page 366for more
information.Used Replacement Wheels
{CAUTION:
Putting a used wheel on your 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.
363

Capacities and Specications
The following approximate capacities are given in English and metric conversions. SeeRecommended
Fluids and Lubricants on page 415for more information. When adding, be sure to fill to the appropriate
level or as recommended in this manual.
See refrigerant charge label under the hood for charge capacity information and requirements.
ApplicationCapacities
English Metric
Air Conditioning Refrigerant R134aFor the air conditioning system refrigerant
charge amount, see the refrigerant
caution label located under the hood.
See your dealer for more information.
Cooling System
4300 V6 11.0 qt 10.4 L
4800 V8, 5300 V8, 5300 V8 Flexible Fuel 13.4 qt 12.7 L
6000 V8 14.8 qt 14.0 L
Cooling System with Rear Heat
4300 V6 14.0 qt 13.2 L
4800 V8, 5300 V8, 5300 V8 Flexible Fuel 16.4 qt 15.5 L
6000 V8 17.8 qt 17.0 L
398

Scheduled Maintenance (cont’d)
Service MaintenanceIMaintenanceII
Check engine coolant and windshield washer fluid levels and add fluid as
needed.••
Perform any needed additional services. See “Additional Required Services”
in this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission fluid level and add fluid as needed.•
Inspect shields, vehicles with GVWR above 10,000 lbs (4 536 kg) only.
See footnote (g).•
Inspect throttle system.See footnote (m).•
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