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Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from short circuits by a
combination of fuses, circuit breakers, and fusible thermal links
in the
wiring itself. This greatly reduces
the chance of fires caused by electrical
problems. See “Fuses and Circuit Breakers’’
in the Index for more
information.
Headlamps
The headlamp wiring is protected by a circuit breaker in the lamp switch.
An electrical overload will cause
the lamps to flicker on and off, or in some
cases to remain
off. If this happens, have your headlamp wiring checked
right away.
Windshield Wipers
The windshield wiper motor is protected by a clrculc DreaKer ana a ruse. 11
the motor overheats due to heavy snow, etc., the wiper will stop until the
motor cools. Although the circuit is protected from electrical overload,
overload due to heavy snow, etc., may cause wiper linkage damage. Always
clear ice and heavy snow from the the windshield before using the
windshield wipers. If the overload
is caused by some electrical problem and
not snow, etc., be sure
to get it fixed.
Power Windows and Other Power Options
Circuit breakers in the fuse panel protect the power windows and other
power accessories. When the current load is too heavy, the circuit breaker
opens and closes. This protects the circuit
until the current load returns to
normal or the problem is fixed.
Trailer Wiring Harness
The standard seven-wire trailer wiring harness is protected by an in-line
fuse in the battery feed wire. This fuse is near the junction block. See
“Trailer Wiring Harness” in the Index for more information.
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Page 346 of 488

Fuse Block
The fuse block access
door is on the driver’s
side edge
of the
instrument panel.
Pull
off the cover to access
the fuse block.
You can remove fuses
with a fuse extractor.
The fuse extractor is
mounted to the fuse
block access door.
To remove fuses if you don’t have a fuse extractor, hold the end of the fuse
between your thumb and index finger and pull straight out.
Be sure to use the correct fuse. If you ever have a problem
on the road and
don’t have a spare fuse, you can “borrow” one
of the correct value. Just pick
some feature of your vehicle that
you can get along without-like the radio
or cigarette lighter-and use its fuse, if
it is of the value you need. Replace
it as soon as you can. See “Fuses and Circuit Breakers” in the Tndex for
more information.
Specification Charts
Replacement Parts
Replacement part numbers listed in this section are based on the latest
information available at the time
of printing, and are subject to change. If a
part listed in this manual is not the same as the part used in your vehicle
when it was built,
or if you have any questions, please contact your GM
truck dealer.
These specifications are for information
only. If you have any questions, see
the service manual for the chassis or refer
to the body manufacturer’s
publications.
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Engine Identification - Gasoline Engines
Engine
Type
VIN Code
Fuel System
Emissions
5.0L
V8
H
TBI? LD
"Light Duty Emissions with
8,500 lbs. (3 850 Kg) GVWR and below.
**Heavy Duty Emissions over 8,500 lbs. (3 850 Kg) GVWR.
?Throttle Body Injection
Engine Identification - Gasoline Engines (cont.)
Engine
Type
VIN Code
Fuel System
Emissions 7.4L
V8
N
TBI?
LD*/HD**
"Light Duty Emissions with 8,500 lbs. (3 850 Kg) GVWR and below.
""Heavy Duty Emissions over
8,500 lbs. (3 850 Kg) GVWR.
?Throttle Body Injection
Engine Identification - Diesel Engines
Engine
Type
VIN Code
Fuel System
6.5L
V8
P
Diesel
6.5L
V8 S
Turbo Diesel
6.5L
V8
F
Turbo Diesel
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Wheel Nut Torque
MODEL
C 1500
K 1500 & C-K 2500
C-K 2500
(w/CGP)
C-K 3500
-Single Rear Wheels
C3500
-Dual Rear Wheels
C3500 HD
-Front
-Rear
DESCRIPTION
5 bolts ( 14mm)
6 bolts (14mm)
8 bolts ( 14mm)
8 bolts ( 14mm)
8 bolts (14rnm)
5 bolts (518 in.)
10 bolts (5/8 in.)
Cooling System Capacity
ENGINE
4.3L
5 .OL
5.7L
6.5L
6.5L
6.5L
7.4L
7.4L w/3500
HD
VIN
Z
H
K
P
S
F
N
N
TORQUE
120 ft. lbs. (1 60 Nmm)
120 ft. lbs. (160 Nmm)
120 ft. lbs. (160 Nom)
120
ft. lbs. (1 60 Nom)
140 ft. lbs. ( 190 Nmm)
175 ft. lbs. (240 Nom)
175 ft. lbs. (240 Nom)
QUANTITY*
13 Quarts (12.3 Liters)
17.5 Quarts (16.6
Liters)
17.5 Quarts (16.5
Liters)
23.5 Quarts (22.2
Liters)
23.5 Quarts (22.2
Liters)
23.5 Quarts (22.2
Liters)
25
Quarts (23.5 Liters)
28.5
Quarts (27 Liters)
After refill, the level
MUST be checked as outlined under “Engine Cooling
System”
in Section 5.
*All quantities are approximate.
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CranKcase Capacity
ENGINE
4.3L 5 .OL
5.7L“
6.5L
6.5L
6.5L
7.4L>$
VIN
Z
€4
K
P
S
F
N
QUANTITY WITH
FILTER*
4.5 Quarts (4.3 Liters)
5 Quarts (4.8 Liters)
5 Quarts (4.8 Liters)
7 Quarts (6.5 Liters)
7 Quarts
(6.5 Liters)
7 Quarts (6.5 Liters)
7 Quarts (6.5 Liters)
After refill, the level
MUST be checked as outlined under “Engine Oil And
Filter Recommendations”
in Section 5.
All quantities are approximate.
“Add one additional quart for
C3500 HD Models.
+Oil filter should be changed at EVERY oil change.
Fuel Tank Capacity
TYPE
Gasoline/Diesel
with Short Bed
with Long Bed
Crew Cab
Standard
Chassis-Cab Models
Standard (Side Tank)
Optional (Rear Tank)
3500 HD Models
Standard (Side Tank)
Optional (Rear Tank)
QUANTITY
26 Gallons (98 Liters)
34 Gallons
(1 28 Liters)
34 Gallons
(1 28 Liters)
23 Gallons (87 Liters)
3
1 Gallons (1 17 Liters)
23 Gallons (87 Liters)
3 1 Gallons ( 117 Liters)
All quantities are
for a completely dry tank and are approximate.
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Service Replacement Part and Filter
Recommendations
- Gasoline Engines
Engine 4.3L
VTN Z
Oil Filter PFS2
Air Cleaner
A 178CW
Filter
PCV Valve CV789C
Spark
Plugs* .CR43TS
Fuel Filter GF48
1
Radiator Cap
RC36
5.0L
H
PF12183-
A348C
cv774c
.CR43TS
GF48
1
RC36
5.7L
K
PF1218q A348C
cv774c
.CR43TS GF38
1
RC36
+Four Wheel Drive Vehicle
- use a PFS2 oil filter
Wse AC copper-cored resistor type spark plugs
Service Replacement Part and Filter
Recommendations
- Diesel Engines
Engine 6.5L 6.5L
VIN P S
Oil Filter PF1218
PF1218
Air Cleaner A644C
A 1236C
Fuel Filter TP
1006 TP
1 006
Surge
Tank Cap RC33 RC33
7.41
N
PF1218
A348C
cv774c
.CR43TS GF48
I
RC36
6.51
F
PF1218
A 1236C
TP
I006
RC33
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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. For additional information, see
your “Warranty and Owner Assistance Information” booklet,
NOTICE:
R-134A refrigerant is not compatible with R-12 refrigerant in
an air conditioning system.
R-12 in an R-134A system will cause
compressor failure, refrigerant oil sludge,
or poor air
conditioning system performance.
Air Conditioning
TYPE
Refrigerant R-
Refrigerant Capacity
134A
QTY
2.25 lbs. (1.020 kg)
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Fuse Block
I 25AMP I CLEAR I
I 30AMP I GREEN I
f
.
D
01
o7 o2
o3
[I8 o9
0
[I,,
0.
0 lo
0 22
0
0 23
0 l2
0 24
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