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Circuit Breaker Usage
1 Stoplamps
2 Center High Mounted Stop Lamps
3 Parking Lamps
4 Powertrain Control Module
5 Auxiliary Wiring
6 Heater/Air Conditioning
7 Hazard Warning FlashersCircuit Breaker Usage
8 Power Post
9 Courtesy Lamps
10Warning Lights, Gages and
Indicators
11 Crank
12 Rear Axle
13Trailer Turn Signals/Hazard Warning
Flashers
14 Radio/Chime
15 Daytime Running Lamps
16 Air Bag System
17 Exterior/Interior Lamps
18 Parking Brake
19 Accessory Power
20 Ignition
21 Sidemarker Lamps
22 Turn Signal/Backup Lamps
23 Transmission
24 Chassis
A Spare
B Spare Fuse Block 2
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Relay Usage
PTO Power Take-Off
REVERSE Reverse
NEUTRAL
STARTNeutral Start
Fuse Usage
RR DEFOG Rear Defog
ENG 1 Engine 1
ENG 3 Engine 3
PCM-B Powertrain Control Module
BLANK Empty
ENG 4 Engine 4
ENG 2 Engine 2
HTD FUEL Heated Fuel
BLANK EmptyFuse Usage
BLANK Empty
BLANK Empty
A/C COMP Air Conditioning Compressor
ABS 1 Anti-Lock Brake System 1
ABS 2 Anti-Lock Brake System 2
ABS 3 Anti-Lock Brake System 3
ENGINE Engine
E/A PUMP Electronic/Automatic Pump
HORN Horn
NOTE 2L18/LB7 Fuel, LG4 Powertrain
Control Valve, LG5 Electronic
Control Module
BLANK Empty
STUD A Spare
STUD B Spare
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Cooling System Capacity
The following approximate capacities are given in English and metric conversions. Please refer toPart C:
Recommended Fluids and Lubricants on page 6-29for more information.
ApplicationCapacities
English Metric
C4/C5 Models
8.1L with manual transmission 30.1 quarts 28.5 liters
8.1L with automatic transmission 29.8 quarts 28.2 liters
6.6L with manual transmission 27.6 quarts 26.1 liters
6.6L with automatic transmission 27.3 quarts 25.8 liters
C6/C7/C8 Models
8.1L with manual transmission 33.3 quarts 31.5 liters
8.1L with manual transmission, air conditioning and
increased cooling34.9 quarts 33.0 liters
8.1L with automatic transmission 32.5 quarts 30.8 liters
7.8L 200–230 hp engine with manual transmission 31.6 quarts 29.9 liters
7.8L 200–230 hp engine with manual transmission, air
conditioning and increased cooling35.3 quarts 33.4 liters
C6/C7/C8 Models
7.8L 200–215 hp engine with automatic transmission 33.7 quarts 31.9 liters
7.2L 175–230 hp engine with manual transmission 29.3 quarts 27.7 liters
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ApplicationCapacities
English Metric
7.2L 175–230 hp engine with manual transmission, air
conditioning and increased cooling33.0 quarts 31.2 liters
7.2L 175–210 hp engine with automatic transmission 31.4 quarts 29.7 liters
7.8L 250–275 hp engine with manual transmission 34.9 quarts 33.0 liters
7.8L 250–275 hp engine with manual transmission, air
conditioning and increased cooling35.4 quarts 33.5 liters
7.8L 230–275 hp engine with automatic transmission 33.3 quarts 31.5 liters
7.2L 250–300 hp engine with manual transmission 32.8 quarts 31.0 liters
7.2L 250–300 hp engine with manual transmission, air
conditioning and increased cooling33.3 quarts 31.5 liters
7.2L 250–300 hp engine with automatic transmission 31.2 quarts 29.5 liters
Air Conditioning Refrigerant R134a 2.1 lbs. 1.0 kg
It is recommended that service work on your air conditioning system be performed by a qualified technician.
R134a 2.1 lbs. (1.0 kg)
Use Refrigerant Oil, R143a Systems
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Maintenance Schedule
Introduction
Important: Keep engine oil at the proper level and
change as recommended.
Have you purchased the GM Protection Plan? The Plan
supplements your new vehicle warranties. See your
Warranty and Owner Assistance booklet or your dealer
for details.
Maintenance Requirements
Maintenance intervals, checks, inspections and
recommended fluids and lubricants as prescribed in this
manual are necessary to keep your vehicle in good
working condition. Any damage caused by failure
to follow scheduled maintenance may not be covered by
warranty.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. 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, be sure to maintain your vehicle properly.
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How This Section is Organized
This maintenance schedule is divided into four parts:
Part A: Scheduled Maintenance Services”:explains
what to have done and how often. Some of these
services can be complex, so unless you are technically
qualified and have the necessary equipment, you
should let your GM dealer’s service department do
these jobs.
Your GM dealer has GM-trained and supported
service people that will perform the work using genuine
GM parts.
{CAUTION:
Performing maintenance work on a vehicle can
be dangerous. In trying to do some jobs, you
can be seriously injured. Do your own
maintenance work only if you have the
required know-how and the proper tools and
equipment for the job. If you have any doubt,
have a quali ed technician do the work.If you want to get the service information, seeService
Publications Ordering Information on page 7-7.
“Part B: Owner Checks and Services”:tells you what
should be checked and when. It also explains what
you can easily do to keep your vehicle in good condition.
“Part C: Recommended Fluids and Lubricants”:
lists some recommended products necessary to
help keep your vehicle properly maintained. These
products, or their equivalents, should be used whether
you do the work yourself or have it done.
“Part D: Maintenance Record”:is a place for you to
record and keep track of the maintenance performed on
your vehicle. Keep your maintenance receipts. They
may be needed to qualify your vehicle for warranty
repairs.
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Part A: Scheduled Maintenance
Services
In this part are scheduled maintenance services which
are to be performed at the mileage intervals specified.
Using Your Maintenance Schedule
We at General Motors want to help keep your vehicle in
good working condition. But we do not know exactly
how you will drive it. You may drive very short distances
only a few times a week. Or you may drive long
distances all the time in very hot, dusty weather. You
may use your vehicle in making deliveries or in
many other ways.
Because of all the different ways people use their
vehicles, maintenance needs vary. You may need more
frequent checks and replacements. So please read
the following and note how you drive. If you have any
questions on how to keep your vehicle in good condition,
see your dealer.
This part tells you the maintenance services you should
have done and when to schedule them.
When you go to your dealer for your service needs, you
will know that GM-trained and supported service
people will perform the work using genuine GM parts.The proper fluids and lubricants to use are listed in
Part C. Make sure whoever services your vehicle uses
these. All parts should be replaced and all necessary
repairs done before you or anyone else drives the
vehicle.
This schedule is for vehicles that:
•carry passengers and cargo within recommended
limits. You will find limits on your vehicle’s GVW
Rating label. SeeLoading Your Vehicle on
page 4-33.
•are driven on reasonable road surfaces within legal
driving limits.
•use the recommended fuel. SeeWhat Fuel to Use
on page 5-8.
Scheduled Maintenance
Supplements
If your vehicle has a Caterpillar®diesel engine, your
owner’s manual is supplemented by the Caterpillar®
Diesel Engine Operation & Maintenance Manual. If your
vehicle has an Allison transmission, your owner’s
manual is supplemented by an Allison
Transmission
®Operator’s Manual. Always refer to these
manuals for related maintenance services.
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10,000 Miles (16 000 km)
❑DURAMAX™ Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first).(2) (3)
15,000 Miles (24 000 km)
❑Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system. See
“Engine Oil (Gasoline Engine)” in the
Index.(3) (9)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(12)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (6)
❑Gasoline Engine: Inspect engine air cleaner filter if
you are driving in dusty conditions and replace
filter if necessary. Diesel Engine: Inspect engine air
cleaner filter change indicator. If necessary,
replace the filter. If vehicle is driven in dusty/dirty
conditions, inspect filter change indicator at
every engine oil change. SeeEngine Air
Cleaner/Filter on page 5-30for more
information.† (3)
❑DURAMAX™ Diesel Only: Replace fuel filter.
❑Steering system service.(13)
❑Front and rear suspension service.(14)
❑Spring-to-axle U-bolts and shackle bolts service.(16)❑Exhaust system service (or every 6 months,
whichever occurs first).(3) (4) (17)
❑Wheels and tires service.(15)
❑Hydraulic brake service (or every 6 months,
whichever occurs first).(7) (46)
❑Parking brake service (or every 6 months, whichever
occurs first).(8)
❑Air brake service (or every 6 months, whichever
occurs first).(39)
❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(40)
❑Check air brake relay valve operation and check for
leaks (or every month, or every 300 hours, whichever
occurs first).
❑Clean air brake application valve (or every 3 months,
or every 300 hours, whichever occurs first). Lubricate
linkage.
❑Air brake chamber service (or every 2 months,
whichever occurs first).(41)
❑Trailer brake hand control valve service (or every
3 months, or every 900 hours, whichever occurs
first).(42)
❑Thermostatically controlled engine cooling fan
service.(4) (20)
❑Shields and underhood insulation service.(4) (5) (21)
6-6