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Underhood Fuse Block
When a circuit goes out, the problem could be in either
the primary or secondary underhood fuse blocks.
These blocks uses blade-type fuses.
Both underhood fuse
blocks are located in the
engine compartment,
on the passenger’s side of
the vehicle.
To access the fuse blocks, gently squeeze both sides of
the cover to unlatch the tabs at the top. Then, unsnap
both attachments at the bottom and remove the cover.
Be sure to replace fuses with fuses of the same
rating. Do not use fuses of higher amperage than those
indicated on the fuse block.Relay Usage
NOTE 1 LG4 Powertrain Control Valve,
L18/LB7 Fuel Pump, LG5 Heated
Fuel
IGN B Ignition
STARTER Starter
HORN Horn
IGN A Ignition Primary Underhood
Fuse Block
Primary Underhood Fuse Block
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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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Fuse Usage
IGN 1 Ignition 1
IGN 4 Ignition 4
IGN 3 Ignition 3
BATT/HAZ Battery/Hazard Warning Flashers
HEADLAMP Headlamps
LIGHTING Interior/Exterior Lamps
HVAC Comfort Control System
NOTE C4/C5 Electric Brake,
C6/C7/C8 Brake Lamps
Capacities and Speci cations
Capacities and Speci cations
Engine RPO
7.2L L6 HEUI Fuel System LG5
8.1L V8 SPFI Fuel System L18
7.8L L6 Common Rail Fuel System LG4
6.6L V8 Common Rail Fuel System LB7/LLY Secondary Underhood
Fuse Block
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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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Engine Oil with Filter Capacity
ApplicationCapacities
English Metric
7.2L** 30.0 quarts 28.4 liters*
8.1** 6.5 quarts 6.1 liters
7.8L** 23.8 quarts 22.5 liters
6.6L** 14.6 quarts 13.8 liters
*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
ApplicationCapacities
English Metric
C4/C5 Models
Standard*
Optional
Optional
Optional40 gallons
40 gallons
60 gallons
80 gallons151.4 liters
151.4 liters
227.1 liters
302.8 liters
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Fuel Tank Capacity (cont’d)
ApplicationCapacities
English Metric
C6/C7/C8 Models
Standard
Optional
Optional
Optional†
Optional**
Optional&50 gallons
35 gallons
50 gallons
70 gallons
75 gallons
100 gallons189.2 liters
132.4 liters
189.2 liters
264.8 liters
283.8 liters
378.5 liters
*One 25-gallon (94.6 L) tank and one 15-gallon (56.8 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
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Transmission Fluid Capacity
For manual transmissions, the correct fluid level is to the bottom of the fluid fill plug opening. The fluid capacity will
vary, due to the angle of the transmission, with the vehicle. For automatic transmissions, see the Allison Automatic
Transmission Operator’s Manual for fluid check and maintenance information.
ApplicationCapacities
English Metric
Manual Transmission
ZF S6–650 12.7 pints 6.0 liters
RT6609 12.5 pints 5.9 liters
RT8709B 25.1 pints 11.8 liters
FS4205A, FS4205B, FS4205C 11.1 pints 5.3 liters
FS5205A, FS5205C 11.6 pints 5.5 liters
FS5406 18.4 pints 8.7 liters
FS6305A, FS6305B 18.4 pints 8.7 liters
FS6406 18.4 pints 8.7 liters
FS8406 18.5 pints 8.8 liters
RT8908LL 29.1 pints 13.8 liters
Automatic Transmission
MD 3060 P 52.0 pints 24.6 liters*
MD 3560 P 52.0 pints 24.6 liters*
1000 Series 35.0 pints 13.5 liters*
2000 Series 35.0 pints 13.5 liters*
2200 Series 35.0 pints 13.5 liters*
2400 Series 35.0 pints 13.5 liters*
*Add two pints (one liter) when changing spin-on or remote filter.
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