
(2) Install the exhaust pipe onto exhaust mani-
folds, tighten 31 N´m (23 ft. lbs.).
(3) Tighten all clamp nuts to 48 N´m (35 ft. lbs.)
torque.
(4) Lower the vehicle.
(5) Start the engine and inspect for exhaust leaks
and exhaust system contact with the body panels. A
minimum of 25.4 mm (1.0 in.) is required between
exhaust system components and body/frame parts.
Adjust the alignment, if needed.
CATALYTIC CONVERTER - 5.9L
HEAVY DUTY/8.0L
DESCRIPTION
The stainless steel catalytic converter is located
under the vehicle, attached to the exhaust pipe(s).
OPERATION
The catalytic converter captures and burns any
unburned fuel mixture exiting the combustion cham-
bers during the exhaust stroke of the engine. This
process aids in reducing emissions output.
REMOVAL
(1) Raise and support vehicle.
(2) Saturate the bolts and nuts with heat valve
lubricant. Allow 5 minutes for penetration.
(3) Remove clamps and nuts (Fig. 5) (Fig. 6).
(4) Remove the catalytic converter.
Fig. 4 Catalytic Converter and Exhaust Pipe 3.9L,
5.2L and 5.9L Light Duty ( California )
1 - BOLT
2 - RETAINER
3 - EXHAUST MANIFOLD
4 - NUT
5 - MINI CATALYTIC CONVERTER
6 - CATALYTIC CONVERTER WITH PIPES
Fig. 5 Catalytic Converter 5.9L Heavy Duty
1 - DOWN PIPE RIGHT
2 - CLAMP
3 - CLAMP
4 - HANGER ASSY. DUAL CLAMP
5 - MUFFLER
6 - EXTENSION PIPE
7 - CATALYTIC CONVERTER
8 - DOWN PIPE LEFT
Fig. 6 Catalytic Converter 8.0L
1 - CLAMPS
2 - CATALYTIC CONVERTERS
3 - MUFFLER
4 - HANGER ASSY. DUAL CLAMP
5 - EXTENSION PIPES
6 - DOWN PIPE
11 - 6 EXHAUST SYSTEMBR/BE
CATALYTIC CONVERTER - 3.9L/5.2L/5.9L (Continued)

INSPECTION
Look at the stainless steel body of the converter,
inspect for bulging or other distortion that could be a
result of overheating. If the converter has a heat
shield attached make sure it is not bent or loose.
If you suspect internal damage to the catalyst, tap-
ping the bottom of the catalyst with a rubber mallet
may indicate a damaged core.
INSTALLATION
(1) Assemble converter and clamps loosely in
place.
(2) Tighten all clamp nuts to 48 N´m (35 ft. lbs.)
torque.
(3) Lower the vehicle.
(4) Start the engine and inspect for exhaust leaks
and exhaust system contact with the body panels. A
minimum of 25.4 mm (1.0 in.) is required between
exhaust system components and body/frame parts.
Adjust the alignment, if needed.
EXHAUST PIPE - 3.9L/5.2L/
5.9L
REMOVAL
(1) Raise and support the vehicle.
(2) Saturate the bolts and nuts with heat valve
lubricant. Allow 5 minutes for penetration.
(3) Remove exhaust pipe to manifold bolts, retain-
ers and nuts (Fig. 7).
(4) Remove the clamp nuts (Fig. 7).
(5) Remove the exhaust pipe.
INSPECTION
Discard rusted clamps, broken or worn supports
and attaching parts. Replace a component with orig-inal equipment parts, or equivalent. This will assure
proper alignment with other parts in the system and
provide acceptable exhaust noise levels.
INSTALLATION
(1) Position the exhaust pipe for proper clearance
with the frame and underbody parts. A minimum
clearance of 25.4 mm (1.0 in.) is required.
(2) Position the exhaust pipe to manifold. Install
the bolts, retainers and nuts. Tighten the nuts to 31
N´m (23 ft. lbs.) torque.
(3) Tighten the clamp nuts to 48 N´m (35 ft. lbs.)
torque.
(4) Lower the vehicle.
(5) Start the engine and inspect for exhaust leaks
and exhaust system contact with the body panels.
Adjust the alignment, if needed.
Fig. 7 Exhaust Pipe 3.9L,5.2L, 5.9L Light Duty
1 - EXHAUST PIPE WITH CATALYTIC CONVERTER
2 - CLAMP
3 - MUFFLER
BR/BEEXHAUST SYSTEM 11 - 7
CATALYTIC CONVERTER - 5.9L HEAVY DUTY/8.0L (Continued)

proper alignment with other parts in the system and
provide acceptable exhaust noise levels.
INSTALLATION
(1) Install the exhaust pipe into the transmission
support and onto the turbocharger flange (Fig. 11).
(2) Install the exhaust pipe-to-turbocharger elbow
bolts and tighten to 31 N´m (23 ft. lbs.) torque.
(3) Install the extension pipe and clamp to the
exhaust pipe using a new clamp and tighten the
clamp nuts to 48 N´m (35 ft. lbs.) torque.
(4) Lower the vehicle.
(5) Connect the battery negative cables.
(6) Start the engine and inspect for exhaust leaks
and exhaust system contact with the body panels. A
minimum of 25.4 mm (1.0 in.) is required. Adjust the
alignment, if needed.
HEAT SHIELDS
DESCRIPTION
There are two types of heat shields used. One is
stamped steel the other is molded foil sheets. The
shields attach to the vehicle around the exhaust sys-
tem to prevent heat from the exhaust system fromentering the passenger area and other areas where
the heat can cause damage to other components.
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the nuts or bolts holding the exhaust
heat shield to the floor pan, crossmember or bracket.
(3) Slide the shield out around the exhaust system.
INSTALLATION
(1)Position the exhaust heat shield to the floor pan,
crossmember or bracket and install the nuts or bolts.
(2)Tighten the nuts and bolts 11 N´m (100 in. lbs.).
(3) Lower the vehicle.
MUFFLER - 3.9L/5.2L/5.9L/8.0L
REMOVAL
(1) Raise and support the vehicle.
(2) Saturate the clamp nuts with heat valve lubri-
cant. Allow 5 minutes for penetration.
(3) Disconnect the muffler hanger (Fig. 12) (Fig.
13).
(4) Remove clamps and nuts (Fig. 12) (Fig. 13).
(5) Remove the muffler.
Fig. 12 Muffler for 3.9L, 5.2L and 5.9L-Light Duty Engines
1 - TAILPIPE
2 - CLAMP
3 - MUFFLER LIGHT DUTY
11 - 10 EXHAUST SYSTEMBR/BE
EXHAUST PIPE - 5.9L DIESEL (Continued)

(3) Remove the front support bracket.
(4) Discharge the A/C system (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - STAN-
DARD PROCEDURE) and remove the A/C condenser
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING/A/C CONDENSER - REMOVAL) (Fig.
29) (if A/C equipped) .
(5) Remove the transmission auxiliary cooler (Fig.
29) (Refer to 7 - COOLING/TRANSMISSION/TRANS
COOLER - REMOVAL).
(6) Remove the boost tubes from the charge air
cooler (Fig. 30).
(7) Remove the charge air cooler bolts. Pivot the
charge air cooler forward and up to remove.
CLEANING
CAUTION: Do not use caustic cleaners to clean the
charge air cooler. Damage to the charge air cooler
will result.
NOTE: If internal debris cannot be removed from
the cooler, the charge air cooler MUST be replaced.
(1) If the engine experiences a turbocharger failure
or any other situation where oil or debris get into the
charge air cooler, the charge air cooler must be
cleaned internally.
(2) Position the charge air cooler so the inlet and
outlet tubes are vertical.
(3) Flush the cooler internally with solvent in the
direction opposite of normal air flow.(4) Shake the cooler and lightly tap on the end
tanks with a rubber mallet to dislodge trapped
debris.
(5) Continue flushing until all debris or oil are
removed.
(6) Rinse the cooler with hot soapy water to
remove any remaining solvent.
(7) Rinse thoroughly with clean water and blow
dry with compressed air.
INSPECTION
Visually inspect the charge air cooler for cracks,
holes, or damage. Inspect the tubes, fins, and welds
for tears, breaks, or other damage. Replace the
charge air cooler if damage is found.
Pressure test the charge air cooler, using Charge
Air Cooler Tester Kit #3824556. This kit is available
through CumminstService Products. Instructions
are provided with the kit.
INSTALLATION
(1) Position the charge air cooler. Install the bolts
and tighten to 2 N´m (17 in. lbs.) torque.
Fig. 29 Condenser and Transmission Auxiliary
Cooler
1 - A/C CONDENSOR
2 - TRANSMISSION COOLER
3 - INTERCOOLER
Fig. 30 Air Intake System Tubes
1 - CLAMP
2 - INTERCOOLER INLET DUCT
3 - CLAMP
4 - VALVE COVER
5 - AIR INLET HOUSING
6 - CLAMP
7 - INTERCOOLER OUTLET DUCT
8 - CLAMP
9 - INTERCOOLER
11 - 18 EXHAUST SYSTEMBR/BE
CHARGE AIR COOLER AND PLUMBING (Continued)

FRAME & BUMPERS
TABLE OF CONTENTS
page page
BUMPERS
DESCRIPTION............................1
FRONT AIR DAM
REMOVAL...............................1
INSTALLATION............................2
FRONT FASCIA
REMOVAL...............................2
INSTALLATION............................2
ADJUSTMENT............................2
FRONT LOWER FASCIA
REMOVAL...............................3
INSTALLATION............................3
FRONT FASCIAÐSPORT
REMOVAL...............................3
INSTALLATION............................3
FRONT BUMPER
REMOVAL...............................3
INSTALLATION............................4
FRONT BUMPERÐSPORT
REMOVAL...............................4
INSTALLATION............................4REAR BUMPER
REMOVAL...............................5
INSTALLATION............................5
FRAME
DESCRIPTION............................6
SPECIFICATIONS.........................7
CAB CHASSIS ADAPTER BRACKET
REMOVAL...............................9
INSTALLATION............................9
FRONT TOW HOOK
REMOVAL...............................9
INSTALLATION...........................10
SPARE TIRE WINCH
REMOVAL..............................10
INSTALLATION...........................10
TRAILER HITCH
REMOVAL..............................10
INSTALLATION...........................10
TRANSFER CASE SKID PLATE
REMOVAL..............................11
INSTALLATION...........................11
BUMPERS
DESCRIPTION
Bumpers are used at the front and rear of the
vehicle. Bumpers may be chrome or painted.
Bumpers are designed to protect the exterior sheet-
metal in low impact situations. The bumpers are
attached to the frame and provide mounting points
for some optional accessories such as fog lights and
tow hooks.
FRONT AIR DAM
REMOVAL
(1) Remove Pin-type fasteners attaching air dam
to bottom of front bumper (Fig. 1).
(2) Remove screws attaching air dam to bottom of
front bumper.
(3) Separate air dam from bumper.
BR/BEFRAME & BUMPERS 13 - 1

(1) Be sure fuel tank contains fuel before starting
test. If tank is empty or near empty, amperage read-
ings will be incorrect.
(2) Obtain LCS adapter.
(3) Plug cable from LCS adapter into DRB scan
tool at SET 1 receptacle.
(4) Plug DRB into vehicle 16±way connector (data
link connector).
(5) Connect (-) and (+) test cable leads into LCS
adapter receptacles. Use10 amp (10A +)receptacle
and common (-) receptacles.
(6) Gain access to MAIN MENU on DRB screen.
(7) Press DVOM button on DRB.
(8) Using left/right arrow keys, highlight CHAN-
NEL 1 function on DRB screen.
(9) Press ENTER three times.
(10) Using up/down arrow keys, highlight RANGE
on DRB screen (screen will default to 2 amp scale).
(11) Press ENTER to change 2 amp scale to 10
amp scale.This step must be done to prevent
damage to DRB scan tool or LCS adapter
(blown fuse).
(12) Remove cover from Power Distribution Center
(PDC).
(13) Remove fuel pump relay from PDC. Refer to
label on PDC cover for relay location.
WARNING: BEFORE PROCEEDING TO NEXT STEP,
NOTE THE FUEL PUMP WILL BE ACTIVATED AND
SYSTEM PRESSURE WILL BE PRESENT. THIS WILL
OCCUR AFTER CONNECTING TEST LEADS FROM
LCS ADAPTER INTO FUEL PUMP RELAY CAVITIES.
THE FUEL PUMP WILL OPERATE EVEN WITH IGNI-
TION KEY IN OFF POSITION. BEFORE ATTACHING
TEST LEADS, BE SURE ALL FUEL LINES AND
FUEL SYSTEM COMPONENTS ARE CONNECTED.
CAUTION: To prevent possible damage to the vehi-
cle electrical system and LCS adapter, the test
leads must be connected into relay cavities exactly
as shown in following steps.
Depending upon vehicle model, year or engine con-
figuration, three different types of relays may be
used: Type-1, type-2 and type±3.
(14) If equipped withtype±1 relay(Fig. 13),
attach test leads from LCS adapter into PDC relay
cavities number 30 and 87. For location of these cav-
ities, refer to numbers stamped to bottom of relay
(Fig. 13).
(15) If equipped withtype±2 relay(Fig. 14),
attach test leads from LCS adapter into PDC relay
cavities number 30 and 87. For location of these cav-
ities, refer to numbers stamped to bottom of relay
(Fig. 14).(16) If equipped withtype±3 relay(Fig. 15),
attach test leads from LCS adapter into PDC relay
cavities number 3 and 5. For location of these cavi-
ties, refer to numbers stamped to bottom of relay
(Fig. 15).
Fig. 13 FUEL PUMP RELAY - TYPE 1
TERMINAL LEGEND
NUMBER IDENTIFICATION
30 COMMON FEED
85 COIL GROUND
86 COIL BATTERY
87 NORMALLY OPEN
87A NORMALLY CLOSED
Fig. 14 FUEL PUMP RELAY - TYPE 2
TERMINAL LEGEND
NUMBER IDENTIFICATION
30 COMMON FEED
85 COIL GROUND
86 COIL BATTERY
87 NORMALLY OPEN
87A NORMALLY CLOSED
BR/BEFUEL DELIVERY - GASOLINE 14 - 11
FUEL PUMP (Continued)

(7) Disconnect electrical connectors at all fuel
injectors. To remove connector refer to (Fig. 33). Push
red colored slider away from injector (1). While push-
ing slider, depress tab (2) and remove connector (3)
from injector. The factory fuel injection wiring har-
ness is numerically tagged (INJ 1, INJ 2, etc.) for
injector position identification.
(8) Disconnect fuel line quick-connect fitting at
left-rear end of fuel rail. A special 3/8 inch fuel line
disconnection tool will be necessary.
(9) Remove the six fuel rail mounting bolts from
the lower half of intake manifold (Fig. 34).
(10) Gently rock and pull theleftfuel rail until
the fuel injectors just start to clear the intake mani-
fold. Gently rock and pull therightfuel rail until
the fuel injectors just start to clear the intake mani-
fold. Repeat this procedure (left/right) until all fuel
injectors have cleared the intake manifold.
(11) Remove fuel rail (with injectors attached)
from engine.
(12) Remove the clip(s) retaining the injector(s) to
fuel rail (Fig. 30) or (Fig. 31).
INSTALLATION - 3.9L/5.2L/5.9L
(1) Apply a small amount of engine oil to each fuel
injector o-ring. This will help in fuel rail installation.
(2) Install injector(s) and injector clip(s) to fuel
rail.
(3) Position the fuel rail/fuel injector assembly to
the injector openings on the intake manifold.(4) Guide each injector into the intake manifold.
Be careful not to tear the injector o-ring.
(5) Push therightfuel rail down until fuel injec-
tors have bottomed on injector shoulder. Push the
leftfuel rail down until fuel injectors have bottomed
on injector shoulder.
(6) Install fuel rail mounting bolts.
(7) Connect electrical connector to intake manifold
air temperature sensor.
(8) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 29). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector.
(9) Install the A/C support bracket (if equipped).
(10) Install throttle body to intake manifold. Refer
to Throttle Body installation in this section of the
group.
(11) Install fuel tube (line) at side of fuel rail.
Refer to Quick-Connect Fittings for procedures.
(12) Install air cleaner.
(13) Connect battery cable to battery.
(14) Start engine and check for leaks.
Fig. 33 Remove/Install Fuel Injector Connector
Fig. 34 Fuel Rail Mounting BoltsÐ8.0L V-10
EngineÐTypical
1 - FUEL RAIL
2 - ELECTRICAL CONNECTOR
3 - MOUNTING BOLTS (6)
4 - INTAKE MANIFOLD LOWER HALF
5 - FUEL PRESSURE TEST PORT
6 - FUEL INJECTORS (10)
14 - 18 FUEL DELIVERY - GASOLINEBR/BE
FUEL RAIL (Continued)

INSTALLATION - 8.0L
(1) Apply a small amount of engine oil to each fuel
injector o-ring. This will help in fuel rail installation.
(2) Install injector(s) and injector clip(s) to fuel
rail.
NOTE: The fuel injector electrical connectors on all
10 injectors should be facing to the right (passen-
ger) side of the vehicle (Fig. 34).
(3) Position the fuel rail/fuel injector assembly to
the injector openings on the intake manifold.
(4) Guide each injector into the intake manifold.
Be careful not to tear the injector o-ring.
(5) Push therightfuel rail down until fuel injec-
tors have bottomed on injector shoulder. Push the
leftfuel rail down until fuel injectors have bottomed
on injector shoulder.
(6) Install the six fuel rail mounting bolts into the
lower half of intake manifold. Tighten bolts to 15
N´m (136 in. lbs.) torque.
(7) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 33). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector. The injector wir-
ing harness is numerically tagged.
(8) Install upper half of intake manifold. Refer to
Engines for procedures.
(9) Connect main fuel line at fuel rail. Refer to
Quick-Connect Fittings for procedures.
(10) Install ignition coil pack and bracket assem-
bly at intake manifold and right engine valve cover
(four bolts).
(11) Install throttle body to intake manifold. Refer
to Throttle Body removal in this group.
(12) Install throttle body linkage to throttle body.
(13) Install air cleaner tube and housing.
(14) Install negative battery cable at battery.
(15) Start engine and check for leaks.
FUEL TANK
DESCRIPTION
The fuel tank is constructed of a plastic material.
Its main functions are for fuel storage and for place-
ment of the fuel pump module.
OPERATION
All models pass a full 360 degree rollover test
without fuel leakage. To accomplish this, fuel and
vapor flow controls are required for all fuel tank con-
nections.A rollover valve(s) is mounted into the top of the
fuel tank (or pump module). Refer to Emission Con-
trol System for rollover valve information.
An evaporation control system is connected to the
rollover valve(s) to reduce emissions of fuel vapors
into the atmosphere. When fuel evaporates from the
fuel tank, vapors pass through vent hoses or tubes to
a charcoal canister where they are temporarily held.
When the engine is running, the vapors are drawn
into the intake manifold. Certain models are also
equipped with a self-diagnosing system using a Leak
Detection Pump (LDP). Refer to Emission Control
System for additional information.
REMOVAL
WARNING: GASOLINE POWERED ENGINES: THE
FUEL SYSTEM IS UNDER A CONSTANT PRESSURE
EVEN WITH THE ENGINE OFF. BEFORE SERVICING
THE FUEL TANK, FUEL SYSTEM PRESSURE MUST
BE RELEASED. REFER TO THE FUEL SYSTEM
PRESSURE RELEASE PROCEDURE BEFORE SER-
VICING THE FUEL TANK.
Two different procedures may be used to drain fuel
tank (lowering tank or using DRB scan tool). When
equipped with a diesel engine, the DRB scan tool
cannot be used (no electric fuel pump).
The quickest draining procedure involves lowering
the fuel tank.
Gasoline Powered Engines:As an alternative
procedure, the electric fuel pump may be activated
allowing tank to be drained at fuel rail connection.
Refer to DRB scan tool for fuel pump activation pro-
cedures. Before disconnecting fuel line at fuel rail,
release fuel pressure. Refer to the Fuel System Pres-
sure Release Procedure in this group for procedures.
Attach end of special test hose tool number 6541,
6539, 6631 or 6923 at fuel rail disconnection (tool
number will depend on model and/or engine applica-
tion). Position opposite end of this hose tool to an
approved gasoline draining station. Activate fuel
pump and drain tank until empty.
If electric fuel pump is not operating, tank must be
lowered for fuel draining. Refer to following proce-
dures.
(1) Remove fuel tank filler tube cap.
(2) Perform Fuel System Pressure Release proce-
dure as described in this group.
(3) Gasoline Engines: Disconnect negative battery
cable at battery. Diesel Engines: Disconnect both neg-
ative battery cables at both batteries.
(4) Raise vehicle on hoist.
(5) Certain models are equipped with a separate
grounding wire (strap) connecting the fuel fill tube
assembly to the body. Disconnect wire by removing
screw.
BR/BEFUEL DELIVERY - GASOLINE 14 - 19
FUEL RAIL (Continued)