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What to Use
To determine what kind of lubricant to use seePart C:
Recommended Fluids and Lubricants on page 6-31.
Noise Control System
Tampering with Noise Control
System Prohibited
The following information relates to compliance with
federal noise emission standards for vehicles with
a Gross Vehicle Weight Rating (GVWR) of more than
10,000 lbs (4 536 kg). The Maintenance Schedule
provides information on maintaining the noise control
system to minimize degradation of the noise emission
control system during the life of your vehicle. The noise
control system warranty is given in your warranty
booklet.These standards apply only to vehicles sold in the
United States.
Federal law prohibits the following acts or the causing
thereof:
1. The removal or rendering inoperative by any
person, other than for purposes of maintenance,
repair or replacement, of any device or element of
design incorporated into any new vehicle for the
purpose of noise control, prior to its sale or delivery
to the ultimate purchaser or while it is in use; or
2. The use of the vehicle after such device or element
of design has been removed or rendered inoperative
by any person.
Among those acts presumed to constitute tampering are
the acts listed below.
Insulation:
•
Removal of the noise shields or any underhood
insulation.
Engine:
•
Removal or rendering engine speed governor, if the
vehicle has one, inoperative so as to allow engine
speed to exceed manufacturer specifications.
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Other Service Items
Fuel Filter
Fuel Filter/Pressure Regulator
(Gasoline Engines)
The steel fuel filter/pressure regulator is located near
the engine compartment on the driver’s side frame rail.
If your vehicle has a rear steel fuel tank, the fuel
filter/pressure regulator is located near the rear fuel tank,
on the driver’s side frame rail. SeeScheduled
Maintenance on page 6-5for recommended service
intervals.
If your vehicle is equipped with the optional Davco
spin-on type filter, it is located on the driver’s side
frame rail.
Fuel Filter (Diesel Engines)
If you have a diesel engine, your fuel filter is located in
the engine compartment on the driver’s side of the
vehicle, or along the driver’s side frame rail. See “Fuel
Filter Replacement” earlier in this section for further
information.
Also seeScheduled Maintenance on page 6-5for
recommended service intervals.
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Primary Fuel Filter and Water
Separator
Your vehicle may have this
spin-on filter. It is located
on the driver’s side
frame rail.
It has a clear plastic drain bowl at the bottom. Check
the drain bowl occasionally for any water or particles.
To drain the water or to replace the element, follow the
water draining and element replacement procedure
underWater in Fuel on page 5-12.
Secondary Fuel Filter and Heater
Your vehicle may have this fuel filter and fuel heater.
It is mounted on the left side of the engine.
It has a metal drain bowl at the bottom. Occasionally,
check the bowl for any water or particles. To check or
drain the bowl, shut off the engine.
Then push up on the spring-loaded drain valve until
clear fuel is flowing from the valve. The particles or
water will drain out first.
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Secondary Fuel Filter and Water
Separator/Heater
(Caterpillar
®Diesel)
If you have a Caterpillar®
diesel engine, you may
also have this spin-on filter
and fuel separator/heater.
It will be mounted in the
engine compartment on the
driver’s side of the vehicle.
It has a metal drain bowl at the bottom. Occasionally,
check the bowl for any water or particles.To check or drain the bowl, do the following:
•Shut off the engine.
•Push up on the spring loaded drain valve until clear
fuel is flowing from the valve.
The particles or water will drain out first. SeeEngine Oil
(Caterpillar
®Diesel Engine) on page 5-23orEngine
Oil (Gasoline Engine) on page 5-24orEngine Oil
(DURAMAX
®Diesel Engine) on page 5-28orEngine Oil
(Isuzu Diesel Engine) on page 5-32for proper disposal
procedures.
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Page 305 of 384

Vehicle Care/Appearance Materials
(cont’d)
Description Usage
Cleaner WaxRemoves light scratches
and protects finish.
Foaming Tire Shine
Low GlossCleans, shines and
protects in one easy step,
no wiping necessary.
Wash Wax ConcentrateMedium foaming
shampoo. Cleans and
lightly waxes.
Biodegradable and
phosphate free.
Spot LifterQuickly and easily
removes spots and stains
from carpets, vinyl and
cloth upholstery.
Odor EliminatorOdorless spray odor
eliminator used on
fabrics, vinyl, leather and
carpet.
Vehicle Identi cation
Vehicle Identi cation Number (VIN)
This is the legal identifier for your vehicle. It appears on
a plate in the front corner of the instrument panel, on
the driver side. You can see it if you look through the
windshield from outside your vehicle. The VIN also
appears on the Certification/Tire and Service Parts labels
and the certificates of title and registration.
Engine Identi cation
The eighth character in the VIN is the engine code. This
code helps you identify your vehicle’s engine,
specifications, and replacement parts. SeeCapacities
and Specifications on page 5-109for your vehicle’s
engine code.
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Fusible Links
A fusible link is a short piece of wire several gauge
sizes smaller than the circuit it protects. It will melt in an
overload situation, opening the circuit.
Your starter and other circuits have these fusible links.
The size is printed on the insulation. If the insulation
is burned beyond recognition, consult your dealer for the
proper size. Replace a fusible link with one of the same
size and insulation type. Fusible link insulation is a
special purpose high-temperature material.
Some examples of circuits with fusible links are the
hydraulic brake booster motor feed circuit, the generator
output circuit, and the intake heater feed circuit in
vehicles with a diesel engine.
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. This
protects the circuit until the current load returns to normal
or the problem is fixed.
Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses, circuit breakers,
maxi-fuses and fusible links. This greatly reduces the
chance of a fire caused by an electrical problem. There
may be a fuse taped to the wiring harness near the
hydraulic brake booster.
Instrument Panel Fuse Block
There are two instrument panel fuse blocks located
behind the instrument panel on the passenger side of
the vehicle.
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.
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Relay Usage
ECU/PTO*Engine Control Unit/Power Take-Off
*Diesel 7.8 DURAMAX
®
BRK LAMPC4/C5 Brake Lamps,
C6/C7/C8 Tractor/Trailer Wiring
DRL Daytime Running Lamps
IGN-4 Ignition
CHMSL Center High Mounted Stoplamp
MRK LTS Sidemarker and Clearance Lamps
HTD/MIRR Heated Mirrors
HTR Diesel Heated Fuel
RT TRN TRLR Passenger Side Trailer Turn Signal
Blank Not Used
LT TRN TRLR Driver Side Trailer Turn Signal
Blank Not Used
Blank Not Used
Blank Not Used
Underhood Fuse Block
When a circuit goes out, the problem could be in either
the primary or secondary underhood fuse blocks.
These blocks use blade-type fuses.
Both underhood fuse blocks are located in the engine
compartment, on the passenger 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.
Notice:Spilling liquid on any electrical components
on your vehicle may damage it. Always keep the
covers on any electrical component.
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.
Primary Underhood Fuse Block
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Fuse Usage
RR DEFOG Rear Defogger
ENG 1 Engine 1
ENG 3 Engine 3 (L18/LF6/LF8)
PCM-B Powertrain Control Module
TCM Transmissions (LF8)
ENG 4 Engine 4 (LMM/LF6/LF8)
ENG 2 Engine 2 (L18/LMM)
HTD FUEL Heated Fuel (LMM)
BLANK Not Used
BLANK Not Used
NOTE 3 Fan Relay (LMM), Emissions (L18)
A/C COMP Air Conditioning Compressor
ABS 1 Antilock Brake System 1
ABS 2 Antilock Brake System 2
ABS 3 Antilock Brake System 3
ENGINE Engine
E/A PUMP Electronic/Automatic Pump
HORN HornFuse Usage
NOTE 2Fuel (L18/LMM), Electronic Control
Module (LF6)
NOTE 4 Electronic Control Module (LF6)
STUD A Spare
STUD B Spare
Relay Usage
NOTE 1 LMM/L18 Fuel Pump Relay
IGN B RELAY Ignition Relay
STARTER
RELAYStarter Relay
HORN RELAY Horn Relay
IGN A RELAY Ignition Relay
PTO/ECU*
RELAYPower Take-Off/Engine Control Unit
(*Diesel 7.8L LF8)
REVERSE
RELAYReverse Relay
FAN RELAY Fan Relay (LMM)
5-107