2003 CHEVROLET C/K fuel

6-86
Replacement Bulbs
It is recommended that you use an ACDelco
type bulb whenever you need to replace one.
If you need a bulb replaced, contact your dealer.
Capacities and Specifications
Engine Specifications
Engine RPO LG5 L18 LG4 LB7
Engine Type 7.2L L6 8.1L V8 7.8L L6 6.6L V8
Fuel System HEUI SPFI Common Rail Common Rail
Firing Order
1
-5-3-6-2-41-8-7-2-6-5-4-31-5-3-6-2-41-2-7-8-4-5-6-3

6-88 Engine Oil with Filter Capacity
Engine Quarts (Liters)
7.2L** 30.0 (28.4)*
8.1L** 6.5 (6.1)
7.8L** 23.8 (22.5 )
6.6L** 14.6 (13.8)
*Additional oil is required with auxiliary oil filter
systems. Make sure to add enough extra oil to fill the
auxiliary oil filter system. For vehicles equipped with
the LUBERFINER 750
-C, add 14 quarts (13.25 L).
** Check fill level on the oil indicator after initial fill to
make sure it is actually full. Oil level may vary
depending on vehicle option content.
Fuel Tank Capacity
C4/C5 Models Gallons (Liters). . . . . . . . . . . . . . . . .
Standard* 41 (155.2). . . . . . . . . . . . . . . . . . . . . . . .
Optional 40 (151.4). . . . . . . . . . . . . . . . . . . . . . . . . .
Optional 60 (227.1). . . . . . . . . . . . . . . . . . . . . . . . . .
Optional 80 (302.8). . . . . . . . . . . . . . . . . . . . . . . . . .
C6/C7/C8 Models Gallons (Liters). . . . . . . . . . . . . .
Standard 50 (189.2). . . . . . . . . . . . . . . . . . . . . . . . .
Optional 35 (132.4). . . . . . . . . . . . . . . . . . . . . . . . . .
Optional 50 (189.2). . . . . . . . . . . . . . . . . . . . . . . . . .
Optional
70 (264.8) . . . . . . . . . . . . . . . . . . . . . . . .
Optional75 (283.8) . . . . . . . . . . . . . . . . . . . . . . . .
Optional& 100 (378.5). . . . . . . . . . . . . . . . . . . . . . .
* One 25
-gallon (94.6 L) tank and one 16-gallon
(60.6 L) tank

Two 35
-gallon (132.4 L) tanks
One 25
-gallon (94.6 L) tank and One 50-gallon
(189.2 L) tank
&Two 50
-gallon (189.2 L) tanks

6-91 Service Replacement Part and Filter Recommendations
Engine 7.2L 8.1L 7.8L 6.6L
RPO LG5 L18 LG4 LB7
Spark Plug
ACDelco

41-983
Gap 0.060 inch (1.52 mm)
Torque 14.75 lb. ft. (20.0 Nm)
Oil Filter
CAT

1R0739 ACDelco
PF454GM Part No. 94392475
ACDelco
PF1218
Air Cleaner Donaldson P522606
ACDelco

A1518CC4/C5 Models:
GM Part No. 88937527
C6/C7/C8 Models:
GM Part
No. 88937548***C4/C5 Models:
GM Part No. 88937527
C6/C7/C8 Models:
GM Part No. 88937548***
Fuel Filter
ACDelco


915 Primary**ACDelco
GF626*GM Part No. 94392474 GM Part No. 97256734

6-92
Engine 7.2L 8.1L 7.8L 6.6L
Power Steering
Fluid FilterGM Part
No. 88892858GM Part
No. 88892858GM Part
No. 88892858GM Part
No. 88892858
Secondary
Fuel FilterCAT

1R0751GM Part
No. 25055052GM Part
No. 15098649
Pressure Caps
RC
-54GM Part
No. 15997145GM Part
No. 15075118GM Part
No. 15075118
*Optional Davco (K28) D350921 spin
-on type filter
located on driver's side frame rail.
**Optional Cold Weather (KUK) Racor B6484GM
spin
-on type filter located on driver's side frame rail.*** Optional air filter (GM Part No. 88937525)
for C6/C7/C8 Models. Fits inside standard size filter
(GM Part No. 88937548) listed previously.

7-4
Part A: Scheduled Maintenance
Services
Using Your Maintenance Schedule
We at General Motors want to help you keep your
vehicle in good working condition. But we don't know
exactly how you'll 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 you should schedule them. If you
go to your dealer for your service needs, you'll 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 these limits on your vehicle's
GVW Rating label. See ªLoading Your Vehicleº in
the Index.

are driven on reasonable road surfaces within legal
driving limits.

use the recommended fuel. See ªFuelº in the Index.
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.

7-6
15,000 Miles (24 000 km)

Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº 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)

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)

Thermostatically controlled engine cooling fan
service. (4)(20)

Shields and underhood insulation service. (4)(5)(21)

L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
20,000 Miles (32 000 km)

DURAMAX Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first). (2)(3)

Air compressor dry element pleated paper air strainer
service (or every 2 months or every 800 hours,
whichever occurs first).
22,500 Miles (36 000 km)

Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº in the Index. (3)(9)

Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)

Chassis lubrication service (or every 6 months,
whichever occurs first). (12)

Inspect door hinge pins and bushings and replace
as necessary.

Cooling system service. Clean the cooling system
filler cap with clean water, clean the core, pressure
test the cap and the system for proper pressure
capability and inspect condition of cooling and
heater hoses and clamps. Replace hoses if cracked,
swollen or damaged.

7-7
Wheel bearing (grease type) service (or every
24 months, whichever occurs first, and whenever
hubs are removed). (23)(46)
Wheels and tires service. (15)
Parking brake service (or every 6 months, whichever
occurs first). (8)
Air intake system service (or every 24 months,
whichever occurs first). (4)(5)(24)
Evaporative Control System service (if equipped) (or
every 24 months, whichever occurs first). (3)(26)

Rear axle air shift motor service. (11)
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)
L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
30,000 Miles (48 000 km)
Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº in the Index. (3)(9)
DURAMAX Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first). (2)(3)
Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)
DURAMAX Diesel Only: Replace fuel filter.
Chassis lubrication service (or every 6 months,
whichever occurs first). (12)
Replace fuel filter(s) (or every 12 months, whichever
occurs first). (3)
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)
(Continued)

7-8
30,000 Miles (48 000 km) (Continued)

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)

C600, C700 and C800 Gasoline Engines Only:
Engine drive belts service (or every 12 months,
whichever occurs first). (18)

Thermostatically controlled engine cooling fan
service. (4)(20)

Shields and underhood insulation service. (4)(5)(21)

L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
37,500 Miles (60 000 km)

Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº in the Index. (3)(9)

Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)

Chassis lubrication service (or every 6 months,
whichever occurs first). (12)

Wheels and tires service. (15)

Parking brake service (or every 6 months, whichever
occurs first). (8)
L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
40,000 Miles (64 000 km)

DURAMAX Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first). (2)(3)

Air compressor dry element pleated paper air strainer
service (or every 2 months or every 800 hours,
whichever occurs first).
45,000 Miles (72 000 km)

Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº in the Index. (3)(9)

Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)

DURAMAX Diesel Only: Replace fuel filter.

Chassis lubrication service (or every 6 months,
whichever occurs first). (12)

Cooling system service. Clean the cooling system
filler cap with clean water, clean the core, pressure
test the cap and the system for proper pressure
capability and inspect condition of cooling and
heater hoses and clamps. Replace hoses if cracked,
swollen or damaged.