2008 CHEVROLET SILVERADO cooling

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

Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(40 000)50,000
(80 000)75,000
(120 000)100,000
(160 000)125,000
(200 000)150,000
(240 000)
Change automatic transmission uid
and lter (normal service).•
Four-wheel drive only: Change transfer
case uid (extreme duty service).
See footnotes (g) and (l).• •••••
Four-wheel drive only: Change transfer
case uid (severe service).
See footnotes (g) and (m).•••
Four-wheel drive only: Change
transfer case uid (normal service).
See footnote (g).•••
Inspect evaporative control system.
An Emission Control Service.
See footnotes † and (k).•••
Replace spark plugs and inspect spark
plug wires.An Emission Control
Service.•
Engine cooling system service
(or every ve years, whichever occurs
rst).An Emission Control Service.
See footnote (i).•
Inspect engine accessory drive belt.
An Emission Control Service.
See footnote (q).•
6-7

Maintenance Footnotes (Gasoline
Engine)
This maintenance section applies to vehicles with a
gasoline engine. If your vehicle has a diesel engine, see
the maintenance schedule section in the DURAMAX
®
Diesel manual.
†The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify the
emission warranty or limit recall liability prior to the
completion of the vehicle’s useful life. We, however, urge
that all recommended maintenance services be
performed at the indicated intervals and the maintenance
be recorded.
#Lubricate the front suspension, steering linkage, and
parking brake cable guides. Control arm ball joints on
2500/3500 series vehicles require lubrication but should
not be lubricated unless their temperature is 10°F
(−12°C) or higher, or they could be damaged. Control arm
ball joints on 1500 series vehicles are maintenance-free.
Vehicles used under severe commercial operating
conditions require lubrication on a regular basis every
3,000 miles (5 000 km).(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chafing, etc. Inspect disc
brake pads for wear and rotors for surface condition.
Inspect drum brake linings/shoes for wear or cracks.
Inspect other brake parts, including drums, wheel
cylinders, calipers, parking brake, etc.
(b)Visually inspect front and rear suspension and
steering system for damaged, loose or missing parts,
signs of wear or lack of lubrication. Inspect power
steering lines and hoses for proper hook-up, binding,
leaks, cracks, chafing, etc. Visually check constant
velocity joints, rubber boots, and axle seals for leaks.
(c)Visually inspect hoses and have them replaced if they
are cracked, swollen, or deteriorated. Inspect all pipes,
fittings and clamps; replace with genuine parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.
(d)Inspect wiper blades for wear, cracking, or
contamination. Clean the windshield and wiper blades, if
contaminated. Replace wiper blades that are worn or
damaged. See Windshield Wiper Blade Replacement on
page 5-67 and Windshield and Wiper Blades on
page 5-120 for more information.
6-8