Page 313 of 436

NOTICE:
Using the wrong fluid can badly damage
brake system parts.
For example, just a few
drops of mineral-based oil, such
as engine
oil, in your brake system can damage brake
system parts
so badly that they’ll have to be
replaced. Don’t let someone put in the
wrong kind of fluid.
If you spill brake fluid on your vehicle’s
painted surfaces, the paint finish can be
damaged. Be careful not to spill brake fluid
on your vehicle. If you do, wash
it off
immediately. See “Appearance Care” in
the Index.
Brake Wear
If you have a C 3500 HD model, it has four-wheel disc
brakes without wear indicators.
If you ever hear a brake
rubbing noise, have the brake linings inspected.
If your pickup is not a
C 3500 HD model, it has front
disc brakes and rear drum brakes. Disc brake pads
(except
C 3500 HD models) have
built-in wear indicators that make a high-pitched
warning sound when the brake pads are worn and new
pads
are needed. The sound may come and go or be
heard all the time your vehicle is moving (except when
you are pushing on
the brake pedal firmly).
The brake wear warning sound means that soon
your brakes won’t work well. That could lead to
an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
NOTICE:
Continuing to drive with worn-out brake pads
could result in costly brake repair.
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Name
ECM-B
RR DEFOG IGN-E
Usage
Fuel Pump, PCMNCM
Rear Window Defogger
Auxiliary Fan Relay Coil,
A/C
Compressor Relay, Hot Fuel
Module, Dual Tanks
Name
FUEL SOL
GLOW PLUG
HORN
AUX FAN
ECM-
1
NC
ENG-
1
LIGHTING
BATT
IGN-A
IGN-B ABS
BLOWER STOP/HAZ
Usage
Fuel Solenoid (Diesel Engine)
Glow plugs (Diesel Engine)
Horn, Underhood Lamps
Auxiliary Fan
Injectors,
PCMNCM
Air Conditioning
lgnition Switch,
EGR, Canister
Purge,
EVRV Idle Coast Solenoid,
Heated
02, Fuel Heater
(Diesel Engine), Water Sensor
(Diesel Engine)
Headlamp and Panel Dimmer
Switch,
Fog and Courtesy Fuses
Battery, Fuse Block Busbar
Ignition Switch
Ignition Switch
Anti-Lock Brake Module
Hi Blower Relay
Stoplamps
6-74
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Fuel Tank Capacity (Approximate)
Type
Short Bed
Long Bed Standard Crew Cab
Chassis-Cab Side Tank
Chassis-Cab Rear Tank 3500
HD Models Side Tank
3500
HD Models Rear Tank
Cooling System Capacity (Approximate)
After refill, the level must be rechecked. See “Cooling
System” in the Index.
Engine
“VORTEC” 4300
“VORTEC”
5000
“VORTEC” 5700
“VORTEC” 7400
“VORTEC”
7400
w/3500 HD
VIN
W
M
R
J
J
Quantity
13 quarts (12.3 L)
17.5 quarts (16.6 L)
17.5 quarts (16.6 L)
25 quarts (23.5 L)
28.5 quarts (27 L)
Crankcase Capacity (Approximate)
After refill, the level must be rechecked. See “Engine
Oil” in the Index.
Engine
“VORTEC” 4300
“VORTEC”
5000
“VORTEC” 5700”
“VORTEC” 7400*
VIN
W
M
R
J
Quantity with Filter?
5 quarts (4.8 L)
5 quarts (4.8 L)
7 quarts (6.5 L)
4.5 quarts (4.3
L)
?Oil
filter should be changed at every oil change.
*Add one additional quart (.946
L) for C-3500 HD Models.
Quantity
26 gallons (98 L)
34 gallons (128 L)
34 gallons (128 L)
22 gallons (83 L)
18 gallons (68 L)
22 gallons (83 L)
18 gallons (68 L)
Air Conditioning Refrigerants
Not all air conditioning refrigerants are the same.
If the
air conditioning system in your vehicle needs
refrigerant, be sure the proper refrigerant
is used.
If you’re not sure, ask your GM dealer.
See the refrigerant charge label under the hood for
information regarding refrigerant capacity.
6-78
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Page 356 of 436
Introduction
IMPORTANT:
KEEP ENGINE OIL
AT THE PROPER
LEVEL AND CHANGE AS
RECOMMENDED
I
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle
in good working condition, but also helps the
environment. All recommended maintenance procedures
are important. Improper vehicle maintenance can
even
affect the quality of the air we breathe. Improper fluid
levels or the wrong tire inflation can increase the level
of emissions from your vehicle. To help protect our
environment, and to keep your vehicle in good
condition, please maintain your vehicle properly.
Have you purchased the GM Protection Plan? The Plan
supplements
your new vehicle warranties. See your
Warranty and Owner Assistance booklet, or your
GM dealer for details.
7-2
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Page 359 of 436

Maintenance Schedule
-
Short Trip/City Definition -- Gasoline Engines
Follow the Short TripKity Maintenance Schedule if any
one of these conditions is true for your vehicle:
Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures
are below freezing.
driving in stop-and-go traffic).
off-road frequently.
Most trips include extensive idling (such as frequent
You operate your vehicle in dusty areas or
You frequently tow a trailer.
If the vehicle is used for delivery service, police, taxi
One of the reasons you should follow this schedule if you
operate
your vehicle under any of these conditions is that
these conditions cause engine
oil to break down soonel:
Short Trip/City Intervals -- Gasoline Engines
Every
3,000 Miles (5 000 km): Engine Oil and Filter
or other commercial application.
Change (or
3 months, whichever occurs first). Chassis
Lubrication (or
3 months, whichever occurs first). Drive
Axle Service (or
3 months, whichever occurs fmt).
Short Trip/City Intervals -- Gasoline Engines
Every 6,000 Miles (10
000 km): Tire Rotation.
Every 15,000 Miles (25 000 km): Shields and
Underhood Insulation Inspection (GVWR above
8,500 lbs. only). Front Wheel Bearing Repack (2WD
only) (or at each brake relining, whichever occurs first).
Every 30,000 Miles (50 000 km): Fuel Filter Replacement.
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (vehicles over
8600 GVWR or
driven under severe conditions only).
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection. Fuel Tank, Cap and Lines
Inspection. Exhaust Gas Recirculation System
Inspection. Evaporative Control System Inspection.
Every 100,000 Miles (166 000 km): Spark Plug Wire
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150,000 Miles (240 000 km): Cooling System
Service (or every
60 months, whichever occurs first).
These intervals only summarize maintenance services.
Be sure to follow the complete maintenance schedule
on the following pages.
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Page 360 of 436

Maintenance Schedule
Follow this maintenance schedule only if none of the
conditions from the Short Trip/City Maintenance
Schedule is true.
Da not use this schedule if the vehicle
is used for trailer towing, driven in a dusty area or used
off paved roads. Use the Short Trip/City schedule for
these conditions.
Driving a vehicle with afully warmed engine under
highway conditions causes engine
oil to break
down slower:
Every 7,500 Miles (12 500 km): Engine Oil and Filter
Change (or every
12 months, whichever occurs first).
Chassis Lubrication (or every 12 months, whichever
occurs first). Drive Axle Service. Tire Rotation.
Underhood Insulation Inspection (GVWR above
8,500 lbs. only).
Every 15,000 Miles (25 OOO km): Shields and
I
1 Long Trip/Highway Intervals -- Gasoline Engines ~~~ ~
~ ~~
Every 30,000 Miles (50 000 km): Fuel Filter
Replacement. Front Wheel Bearing Repack
(2WD only)
(or at each brake relining, whichever occurs fiist).
Transmission Service (vehicles over
8600 GVWR or
driven under severe conditions only).
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection. Fuel
Tank, Cap and Lines
Inspection. Exhaust Gas Recirculation System
Inspection. Evaporative Control System Inspection.
Every 100,000 Miles (166 000 km): Spark Plug Wire
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150,000 Miles (240 000 km): Cooling System
Service (or every
60 months, whichever occurs first).
Every 50,000 Miles (83 000 km): Automatic
These intervals only summarize maintenance services.
Be sure to
follow the complete maintenance schedule
on the following pages.
7-6
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Page 362 of 436

Short TripKity Maintenance Schedule -- Gasoline Engines
** Drive axle service (see “Recommended Fluids and
Lubricants”
in the Index for proper lubricant to use):
0
e
0
0
Locking Differential -- Drain fluid and refill at first
engine oil change. At subsequent oil changes, check
fluid level and add fluid as needed. If driving in
dusty areas
or towing a trailer, drain fluid and refill
every 15,000 miles
(25 000 km).
Standard Differential -- Check fluid level and add
fluid
as needed at every oil change. If driving in
dusty areas or towing a trailer, drain fluid and refill
every
15,000 miles (25 000 km).
More frequent lubrication may be required for
heavy-duty
or off-road use.
3500 HD Models with applications requiring extreme
overloadtrailer towing conditions and high-speed (above
45 mph or 70 km/h) conditions for extended
periods of time must have the drive axle fluid changed every
30,000 miles (50 OOO km). See “Recommended
Fluids and Lubricants” in this section.
3,000 Miles (5 000 km)
0 Change engine oil and filter (or every
3 months, whichever occurs first).
An Emission Control Service.
0 Lubricate chassis components (or every
3 months, whichever occurs first).
(See footnote
#.)
0 Check readfront axle fluid level and add
fluid as needed. Check constant velocity
joints and axle seals for leaking.
(See footnote **.)
DATE ACTUAL MILEAGE SERVICED BY:
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Page 363 of 436
1 Short Trip/City Maintenance Schedule =- Gasoline Engines I
6,000 Miles (10 000 km)
Change engine oil and filter (or every
3 months, whichever occurs first).
An Emission Control Service.
0 Lubricate chassis components (or every
3 months, whichever occurs first).
(See footnote
#.)
0 Check readfront axle fluid level and add fluid
as needed. Check constant velocity joints and
axle seals for leaking. (See footnote
**.)
Rotate tires. See “Tire Inspection and
Rotation” in the Index for proper rotation
pattern and additional information.
(See footnote
+.)
9,000 Miles (15 000 km)
0 Change engine oil and filter (or every
3 months, whichever occurs first).
An Emission Control Service.
0 Lubricate chassis components (or every
3 months, whichever occurs first).
(See footnote
#.)
0 Check readfront axle fluid level and add
fluid as needed. Check constant velocity
joints and axle seals for leaking.
(See footnote
**.)
DATE SERVICED BY: ACTUAL MILEAGE
7-9
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