cooling CHEVROLET SILVERADO 2008 2.G Owner's Manual

Cooling System
If your vehicle has the DURAMAX®Diesel engine, see
the DURAMAX®Diesel manual for more information.
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan
{CAUTION:
An electric engine cooling fan can start even
when the engine is not running. To avoid
injury, always keep hands, clothing, and tools
away from any engine cooling fan.
If the coolant inside the coolant surge tank is boiling,
do not do anything else until it cools down. The vehicle
should be parked on a level surface. Check the
coolant level after the system cools down. Some amount
of coolant may be lost due to overheating.
5.3L Engine (4.3L, 4.8L and 6.0L Similar)
5-35

The coolant level should be at or above 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.
{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.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty.
SeeOverheated Engine Protection Operating Mode
(V8 Engines Only) on page 5-34for information
on driving to a safe place in an emergency.
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 the warranty. Always use
DEX-COOL
®(silicate-free) coolant in the vehicle.
5-36

How to Add Coolant to the Coolant
Surge Tank for Gasoline Engines
If your vehicle has a diesel engine, see “Cooling
System” in the DURAMAX®Diesel Supplement for the
proper coolant ll procedure.
If you have not found a problem yet, check to see
if coolant is visible in the surge tank. 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
surge tank, but be sure the cooling system, including
the coolant surge tank pressure cap, is cool before
you do it. SeeEngine Coolant on page 5-29for more
information.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.
5-37

{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 a proper 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. 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
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.
5-38

Engine Fan Noise
If 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
disengages.You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
If your vehicle has electric cooling fans, you may hear
the fans spinning at low speed during most everyday
driving. The fans may turn off if no cooling is required.
Under heavy vehicle loading, trailer towing, and/or
high outside temperatures, or if you are operating your
air conditioning system, the fans may change to
high speed and you may hear an increase in fan noise.
This is normal and indicates that the cooling system
is functioning properly. The fans will change to low
speed when additional cooling is no longer required.
5-40

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:
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 Specifications
on page 5-133.
SeeChanging a Flat Tire on page 5-94for more
information.
Used Replacement Wheels
{CAUTION:
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.
5-91

Fuses Usage
38 Electric Adjustable Pedals
39 Climate Controls (Battery)
40 Airbag System (Ignition)
41 Amplier
42 Audio System
43Miscellaneous (Ignition), Cruise
Control
44 Not Used
45 Airbag System (Battery)
46 Instrument Panel Cluster
47 Power Take-Off
48Auxiliary Climate Control (Ignition),
Compass-Temperature Mirror
49Center High-Mounted
Stoplamp (CHMSL)
50 Rear Defogger
51 Heated Mirrors
52 SEO B1 Uptter Usage (Battery)Fuses Usage
53Cigarette Lighter, Auxiliary Power
Outlet
54Automatic Level Control Compressor
Relay, SEO Uptter Usage
55 Climate Controls (Ignition)
56Engine Control Module, Secondary
Fuel Pump (Ignition)
J-Case Fuses Usage
57 Cooling Fan 1
58 Not Used
59 Heavy Duty Antilock Brake System
60 Cooling Fan 2
61 Antilock Brake System 1
62 Starter
63 Stud 2 (Trailer Brakes)
64 Left Bussed Electrical Center 1
65 Not Used
5-131

J-Case Fuses Usage
66 Heated Windshield Washer System
67 Four-Wheel Drive System
68Stud 1 (Trailer Connector Battery
Power) (Optional - 40A Fuse
Required)
69 Mid-Bussed Electrical Center 1
70 Climate Control Blower
72 Not Used
73 Left Bussed Electrical Center 2Relays Usage
FAN HI Cooling Fan High Speed
FAN LO Cooling Fan Low Speed
FAN CNTRL Cooling Fan Control
HDLP LO/HID Low-Beam Headlamp
FOG LAMP Front Fog Lamps
A/C CMPRSR Air Conditioning Compressor
STRTR Starter
PWR/TRN Powertrain
FUEL PMP Fuel Pump
PRK LAMP Parking Lamps
REAR DEFOG Rear Defogger
RUN/CRANK Switched Power
5-132

Capacities and Specications
The following approximate capacities are given in English and metric conversions. SeeRecommended Fluids and
Lubricants on page 6-14for more information.
If your vehicle has the DURAMAX
®Diesel engine, see the DURAMAX®Diesel manual for more information.
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
4.3L V6 16.5 qt 15.6 L
4.8L V8 16.9 qt 16.0 L
5.3L V8 16.9 qt 16.0 L
6.0L V8 1500 Series 16.8 qt 15.9 L
6.0L V8 2500, 3500 Series 16.4 qt 15.5 L
Engine Oil with Filter
4.3L V6 4.5 qt 4.3 L
4.8L V8; 5.3L V8; 6.0L V8 6.0 qt 5.7 L
5-133

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil (Gasoline Engine) on page 5-15.
Reset oil life system. SeeEngine Oil Life System on page 5-18.An Emission
Control Service.••
Allison Transmission
®only: Replace external transmission lter at the rst
maintenance service performed on the vehicle.
Lubricate chassis components.See footnote #.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner lter or change indicator (if equipped). If necessary,
replace lter. SeeEngine Air Cleaner/Filter (Gasoline Engines) on page 5-20.
See footnote (p).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 5-83and “Tire Wear Inspection” inAt Least Once a Month on
page 6-11.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid 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).•
6-5