2004 CHEVROLET SILVERADO AIR

Service............................................................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of
Your Vehicle..............................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-7
Fuel E-85 (85% Ethanol).................................5-8
Fuels in Foreign Countries...............................5-9
Filling Your Tank............................................5-9
Filling a Portable Fuel Container.....................5-11
Checking Things Under the Hood....................5-12
Hood Release..............................................5-12
Engine Compartment Overview.......................5-14
Engine Oil...................................................5-20
Engine Air Cleaner/Filter................................5-25
Automatic Transmission Fluid
(Except Allison Transmission
®) ....................5-27
Automatic Transmission Fluid
(Allison Transmission
®) ...............................5-30
Manual Transmission Fluid.............................5-33
Hydraulic Clutch...........................................5-34Engine Coolant.............................................5-35
Coolant Surge Tank Pressure Cap..................5-38
Engine Overheating.......................................5-38
Cooling System............................................5-41
Engine Fan Noise.........................................5-46
Power Steering Fluid.....................................5-46
Windshield Washer Fluid................................5-47
Brakes........................................................5-49
Battery........................................................5-52
Jump Starting...............................................5-53
All-Wheel Drive..............................................5-58
Rear Axle.......................................................5-59
Four-Wheel Drive............................................5-60
Noise Control System.....................................5-61
Tampering with Noise Control System
Prohibited.................................................5-61
Bulb Replacement..........................................5-63
Halogen Bulbs..............................................5-63
Headlamps..................................................5-63
Front Turn Signal, Sidemarker and
Daytime Running Lamps.............................5-65
Roof Marker Lamps......................................5-66
Center High-Mounted Stoplamp (CHMSL)
and Cargo Lamp.......................................5-68
Section 5 Service and Appearance Care
5-1

Doing Your Own Service Work
If you want to do some of your own service work, you
will want to use the proper service manual. It tells
you much more about how to service your vehicle than
this manual can. To order the proper service manual,
seeService Publications Ordering Information on
page 7-11.
Your vehicle has an air bag system. Before attempting
to do your own service work, seeServicing Your Air
Bag-Equipped Vehicle on page 1-83.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeeMaintenance Record on page 6-19.{CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
Be sure to use the proper nuts, bolts and
other fasteners. “English” and “metric”
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.
5-4

Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airow around it. This may cause wind
noise and affect windshield washer performance. Check
with your dealer before adding equipment to the
outside of your vehicle.
Fuel
If your vehicle has a diesel engine, see “Diesel
Fuel Requirements and Fuel System” in the Diesel
Engine Supplement.
For vehicles with gasoline engines, please read this.
Gasoline Octane
For all except the Silverado SS model, use regular
unleaded gasoline with a posted octane of 87 or higher.
If the octane is less than 87, you may get a heavy
knocking noise when you drive. If this occurs, use a
gasoline rated at 87 octane or higher as soon as
possible. Otherwise, you might damage your engine.
A little pinging noise when you accelerate or drive uphill
is considered normal. This does not indicate a problem
exists or that a higher-octane fuel is necessary.
If you are using 87 octane or higher-octane fuel and
hear heavy knocking, your engine needs service.
If you have the Silverado SS model, use premium
unleaded gasoline with a posted octane of 91 or higher
for best performance. You may also use middle
grade or regular unleaded gasoline rated at 87 octane
or higher, but your vehicle’s acceleration may be slightly
reduced. If the octane is less than 87, you may get a
heavy knocking noise when you drive. If this occurs, use
gasoline rated at 87 octane or higher as soon as
possible. Otherwise, you might damage your engine.
5-5

Gasoline Specications
It is recommended that gasoline meet specications
which were developed by automobile manufacturers
around the world and contained in the World-Wide
Fuel Charter which is available from the Alliance of
Automobile Manufacturers at www.autoalliance.org/
fuel_charter.htm. Gasoline meeting these specications
could provide improved driveability and emission control
system performance compared to other gasoline.
In Canada, look for the
“Auto Makers’ Choice”
label on the pump.
California Fuel
If your vehicle is certied to meet California Emission
Standards (see the underhood emission control label),
it is designed to operate on fuels that meet California
specications. If this fuel is not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specications, but emission control system performance
may be affected. The malfunction indicator lamp may
turn on (seeMalfunction Indicator Lamp on page 3-48)
and your vehicle may fail a smog-check test. If this
occurs, return to your authorized GM dealer for
diagnosis. If it is determined that the condition is caused
by the type of fuel used, repairs may not be covered
by your warranty.
Canada Only
5-6

Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work
properly. You should not have to add anything to your
fuel. However, some gasolines contain only the
minimum amount of additive required to meet U.S.
Environmental Protection Agency regulations. General
Motors recommends that you buy gasolines that
are advertised to help keep fuel injectors and intake
valves clean. If your vehicle experiences problems due
to dirty injectors or valves, try a different brand
of gasoline.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the specications described earlier.Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may
be affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer
for service.
5-7

Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
Filling Your Tank
{CAUTION:
Fuel vapor burns violently and a fuel re can
cause bad injuries. To help avoid injuries to
you and others, read and follow all the
instructions on the pump island. Turn off your
engine when you are refueling. Do not smoke
if you are near fuel or refueling your vehicle.
Keep sparks, ames and smoking materials
away from fuel. Do not leave the fuel pump
unattended when refueling your vehicle — this
is against the law in some places. Keep
children away from the fuel pump; never let
children pump fuel.
The fuel cap is located behind a hinged door on the
driver’s side of the vehicle.
To remove the fuel cap, turn it slowly to the left
(counterclockwise). It will require more effort to turn the
fuel cap on the last turn as you loosen it.
5-9

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-25.
B. Coolant Surge Tank. SeeEngine Coolant on
page 5-35.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-25.
D. Engine Oil Dipstick. SeeEngine Oil on page 5-20.
E. Automatic Transmission Dipstick (If equipped).
SeeAutomatic Transmission Fluid (Except Allison
Transmission
®) on page 5-27orAutomatic
Transmission Fluid (Allison Transmission®)on
page 5-30.
F. Fan. SeeCooling System on page 5-41.
G. Engine Oil Fill. SeeEngine Oil on page 5-20.H. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-46.
I. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-53.
J. Remote Positive (+) Terminal. SeeJump Starting on
page 5-53.
K. Brake Fluid Reservoir. SeeBrakes on page 5-49.
L. Clutch Fluid Reservoir (If Equipped). SeeHydraulic
Clutch on page 5-34.
M. Underhood Fuse Block. SeeFuses and Circuit
Breakers on page 5-123.
N. Battery. SeeBattery on page 5-52.
O. Windshield Washer Fluid Reservoir. SeeWindshield
Washer Fluid on page 5-47.
5-15

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-25.
B. Coolant Surge Tank. SeeEngine Coolant on
page 5-35.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-25.
D. Engine Oil Dipstick. SeeEngine Oil on page 5-20.
E. Automatic Transmission Dipstick (If Equipped).
SeeAutomatic Transmission Fluid (Except Allison
Transmission
®) on page 5-27orAutomatic
Transmission Fluid (Allison Transmission®)on
page 5-30.
F. Engine Oil Fill. SeeEngine Oil on page 5-20.
G. Fan. SeeCooling System on page 5-41.H. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-53.
I. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-46.
J. Remote Positive (+) Terminal. SeeJump Starting on
page 5-53.
K. Brake Fluid Reservoir. SeeBrakes on page 5-49.
L. Clutch Fluid Reservoir (If Equipped). SeeHydraulic
Clutch on page 5-34.
M. Underhood Fuse Block. SeeFuses and Circuit
Breakers on page 5-123.
N. Battery. SeeBattery on page 5-52.
O. Windshield Washer Fluid Reservoir. SeeWindshield
Washer Fluid on page 5-47.
5-17