Page 329 of 2889

Two clutch covers are used for all applications. The
281 mm cover (Fig. 27) is used for 3.9L, 5.2L and
5.9L gas engine applications.
The 312.5 mm cover (Fig. 28) is used for 5.9L die-
sel and 8.0L gas engine applications.
OPERATION
The clutch pressure plate assembly clamps the
clutch disc against the flywheel. When the release
bearing is depressed by the shift fork, the pressure
exerted on the clutch disc by the pressure plate
spring is decreased. As additional force is applied,
the bearing presses the diaphragm spring fingers
inward on the fulcrums. This action moves the pres-
sure plate rearward relieving clamp force on the disc.
The clutch disc is disengaged and freewheeling at
this point.
FLYWHEEL
DESCRIPTION
The flywheel (Fig. 29) is a heavy plate bolted to the
rear of the crankshaft. The flywheel incorporates the
ring gear around the outer circumference to mesh
with the starter to permit engine cranking. The rear
face of the flywheel serves as the driving member to
the clutch disc.
OPERATION
The flywheel serves to dampen the engine firing
pulses. The heavy weight of the flywheel relative to
the rotating mass of the engine components serves to
stabilize the flow of power to the remainder of the
drivetrain. The crankshaft has the tendency to
attempt to speed up and slow down in response to
the cylinder firing pulses. The flywheel dampens
these impulses by absorbing energy when the crank-
Fig. 27 Pressure Plate - V6/V8 Gas Engine
1 - COVER
2 - RELEASE FINGERS
3 - PRESSURE PLATE
4 - 281 mm (11 in.)
Fig. 28 Pressure Plate - V10/Diesel Engine
1 - COVER
2 - RELEASE FINGERS
3 - PRESSURE PLATE
4 - 312.5 mm (12.3 in.)
Fig. 29 Flywheel
1 - CRANKSHAFT
2 - RING GEAR
3 - FLYWHEEL
6 - 16 CLUTCHBR/BE
PRESSURE PLATE (Continued)
Page 330 of 2889

shaft speeds and releasing the energy back into the
system when the crankshaft slows down.
DIAGNOSIS AND TESTING - FLYWHEEL
Check flywheel runout whenever misalignment is
suspected. Flywheel runout should not exceed 0.08
mm (0.003 in.). Measure runout at the outer edge of
the flywheel face with a dial indicator. Mount the
indicator on a stud installed in place of one of the fly-
wheel bolts.
Common causes of runout are:
²heat warpage
²improper machining
²incorrect bolt tightening
²improper seating on crankshaft flange shoulder
²foreign material on crankshaft flange
Flywheel machining is not recommended. The fly-
wheel clutch surface is machined to a unique contour
and machining will negate this feature. However,
minor flywheel scoring can be cleaned up by hand with
180 grit emery, or with surface grinding equipment.
Remove only enough material to reduce scoring
(approximately 0.001 - 0.003 in.). Heavy stock removal
isnot recommended.
Replace the flywheel if scoring
is severe and deeper than 0.076 mm (0.003 in.).
Excessive stock removal can result in flywheel crack-
ing or warpage after installation; it can also weaken
the flywheel and interfere with proper clutch release.
Clean the crankshaft flange before mounting the
flywheel. Dirt and grease on the flange surface may
cock the flywheel causing excessive runout. Use new
bolts when remounting a flywheel and secure the
bolts with MopartLock And Seal. Tighten flywheel
bolts to specified torque only. Overtightening can dis-
tort the flywheel hub causing runout.
DISASSEMBLY
NOTE: If the teeth are worn or damaged, the fly-
wheel should be replaced as an assembly. This is
the recommended and preferred method of repair.
In cases where a new flywheel is not readily avail-
able, (V10/Diesel Engine only) a replacement ring
gear can be installed. The following procedure must
be observed to avoid damaging the flywheel and
replacement gear.
WARNING: WEAR PROTECTIVE GOGGLES OR
SAFETY GLASSES WHILE CUTTING RING GEAR.
(1) Mark position of the old gear for alignment ref-
erence on the flywheel. Use a scriber for this pur-
pose.
(2) Remove the old gear by cutting most of the way
through it (at one point) with an abrasive cut-off
wheel. Then complete removal with a cold chisel or
punch.
ASSEMBLY
NOTE: The ring gear is a shrink fit on the flywheel.
This means the gear must be expanded by heating
in order to install it. The method of heating and
expanding the gear is extremely important. Every
surface of the gear must be heated at the same
time to produce uniform expansion. An oven or
similar enclosed heating device must be used. Tem-
perature required for uniform expansion is approxi-
mately 375É F.
CAUTION: Do not use an oxy/acetylene torch to
remove the old gear, or to heat and expand a new
gear. The high temperature of the torch flame can
cause localized heating that will damage the fly-
wheel. In addition, using the torch to heat a replace-
ment gear will cause uneven heating and
expansion. The torch flame can also anneal the
gear teeth resulting in rapid wear and damage after
installation.
WARNING: WEAR PROTECTIVE GOGGLES OR
SAFETY GLASSES AND HEAT RESISTENT GLOVES
WHEN HANDLING A HEATED RING GEAR.
(1) The heated gear must be installed evenly to
avoid misalignment or distortion.
(2) Position and install the heated ring gear on the
flywheel with a shop press and a suitable press
plates.
(3) Place flywheel on work bench and let it cool in
normal shop air. Allow the ring gear to cool down
completely before installation it on the engine.
CAUTION: Do not use water or compressed air to
cool the flywheel. The rapid cooling produced by
water or compressed air will distort or crack the
new gear.
PILOT BEARING
DESCRIPTION
Vehicles equipped with a manual transmission uti-
lize a pilot bearing. This bearing is located in the
back of the engine crankshaft. Depending on the type
of engine or application, the pilot bearing can be a
solid soft metallic bushing or a fully caged needle
bearing. The pilot bearing's main functions are to
support the transmission input shaft, maintain
proper alignment of the clutch assembly and allow
the transmission main shaft to rotate at a different
speed than the engine mounted crankshaft.
BR/BECLUTCH 6 - 17
FLYWHEEL (Continued)
Page 331 of 2889

OPERATION
The pilot bearing supports the transmission input
shaft, maintains proper clutch assembly alignment
and allows the transmission input shaft to rotate at a
different speed (RPM) than the engine mounted
crankshaft.
When the clutch pedal is depressed (with vehicle in
drive mode) the clutch disc slows and stops therefore,
the transmission input shaft slows and stops as well.
The pilot bearing allows the engine crankshaft to
continue to rotate even though the transmission
input shaft is stationary.
REMOVAL
(1) Remove transmission, transfer case, if
equipped, and clutch housing. Refer to Group 21,
Transmission and Transfer Case, for proper proce-
dures.
(2) Remove clutch cover and disc.
(3) Using a suitable blind hole puller, remove pilot
bearing.
INSTALLATION
(1) Clean bearing bore with solvent and wipe dry
with shop towel.
(2) Install new bearing with clutch alignment tool
(Fig. 30). Keep bearing straight during installation.
Do not allow bearing to become cocked. Tap bearing
into place until flush with edge of bearing bore. Do
not recess bearing.
(3) Install clutch cover and disc.
(4) Install clutch housing, transmission and trans-
fer case, if equipped. Refer to Group 21, Transmis-
sion and Transfer Case, for proper procedures.
CLUTCH PEDAL
REMOVAL
(1) Remove retaining clips that secure the brake
and clutch pedals to the push rods (Fig. 31).
(2) Remove the brake and clutch master cylinder
pushrods from the pedals.
(3) Remove knee bolster (Fig. 32) for access to
pedal pivot shaft.
(4) Remove brake lamp switch.
(5) Remove retainer from passenger side of pedal
pivot shaft (Fig. 33).
(6) Push pedal pivot shaft toward driver side of
support only enough to remove clutch pedal. It is not
necessary to remove shaft from pedal support
entirely.
(7) Remove clutch pedal.
Fig. 30 Typical Method Of Installing Pilot Bearing
1 - PILOT BEARING
2 - ALIGNMENT TOOL
3 - LETTER SIDE MUST FACE TRANSMISSION
Fig. 31 Clutch Cylinder Push Rod Attachment
1 - PIN
2 - CLUTCH INTERLOCK WIRE
3 - PUSH ROD
4 - CLIP
6 - 18 CLUTCHBR/BE
PILOT BEARING (Continued)
Page 332 of 2889

INSTALLATION
(1) Inspect bushings in clutch and brake pedals
(Fig. 33). Replace bushings if worn, cracked, or dis-
torted.(2) Lubricate pedal shaft, pedal shaft bore (Fig. 33)
and all bushings with MopartMulti Mileage, or high
temperature bearing grease.
(3) Position clutch pedal in support. Align pedal
with pivot shaft and slide shaft through pedal bush-
ings. Then repeat process for brake pedal.
(4) Slide pedal shaft through support and install
shaft retainer.
(5) Secure push rods to clutch and brake pedals.
(6) Install brake lamp switch in bracket.
(7) Install knee bolster.
LINKAGE
DESCRIPTION
The hydraulic linkage consists of a clutch master
cylinder, reservoir, a clutch slave cylinder and an
interconnecting fluid line 9 (Fig 34).
The clutch master cylinder push rod is connected
to the clutch pedal. The slave cylinder push rod is
connected to the clutch release fork. The master cyl-
inder is mounted on the driver side of the dash panel
adjacent to the brake master cylinder and booster
assembly.
The hydraulic linkage is serviced as an assembly only.
The individual components that form the linkage
assembly cannot be overhauled or serviced separately.
Fig. 32 Knee Bolster RemovalÐTypical
1 - INSTRUMENT PANEL FLANGES
2 - KNEE BOLSTER
Fig. 33 Clutch/Brake Pedal Mounting
1 - PEDAL SUPPORT
2 - SHAFT RETAINER
3 - BRAKE PEDAL
4 - CLUTCH PEDAL
5 - SHAFT RETAINER
6 - PEDAL PIVOT SHAFT
7 - BUSHINGS
Fig. 34 Clutch
1 - DASH PANEL
2 - CYLINDER RESERVOIR
3 - CLUTCH MASTER CYLINDER
4 - SLAVE CYLINDER
5 - CLUTCH HYDRAULIC LINE
BR/BECLUTCH 6 - 19
CLUTCH PEDAL (Continued)
Page 333 of 2889

The clutch fluid reservoir, master cylinder, slave
cylinder and fluid lines are pre-filled with fluid at
the factory during assembly operations.
The hydraulic system should not require additional
fluid under normal circumstances.The reservoir
fluid level will actually increase as normal
clutch wear occurs. Avoid overfilling, or remov-
ing fluid from the reservoir.
Clutch fluid level is checked at the master cylinder
reservoir. An indicator ring is provided on the outside
of the reservoir. With the cap and diaphragm
removed, fluid level should not be above indicator
ring.
To avoid contaminating the hydraulic fluid during
inspection, wipe reservoir and cover clean before
removing the cap.
OPERATION
The clutch linkage uses hydraulic pressure to oper-
ate the clutch. Depressing the clutch pedal develops
fluid pressure in the clutch master cylinder. This
pressure is transmitted to the slave cylinder through
a connecting line. In turn, the slave cylinder operates
the clutch release lever.
The slave cylinder has an integral spring which
preloads the release bearing against the clutch dia-
phragm fingers to maintain zero free-play.
Slave cylinder force causes the release lever to
move the release bearing into contact with the dia-
phragm spring. As additional force is applied, the
bearing presses the diaphragm spring fingers inward
on the fulcrums. This action moves the pressure
plate rearward relieving clamp force on the disc.
REMOVAL
The factory installed hydraulic linkage has a quick
disconnect at the slave cylinder. This fitting should
not be disconnected or tampered with. The hydraulic
linkage is serviced as an assembly only, but it comes
as two pieces to ease installation. Once the clutch
hydraulic line is connected to the slave cylinder, it
should not be disconnected. The individual compo-
nents that form the linkage assembly cannot be over-
hauled or serviced separately.
(1) Raise and support vehicle.
(2) Remove nuts attaching slave cylinder to studs
on clutch housing (Fig. 35).
(3) Remove slave cylinder from clutch housing.
(4) Remove the plastic clip securing the hydraulic
line to the dash panel from the lower dash panel
flange.
(5) Remove the plastic clip securing the hydraulic
line to the dash panel from the upper dash panel
stud.
(6) Lower vehicle.
(7) Disconnect clutch pedal interlock switch wires.(8) Remove retaining clip (Fig. 36).
(9) Slide clutch master cylinder push rod off pedal
pin.
(10) Inspect condition of bushing in the clutch
master cylinder pushrod (Fig. 36). Replace the clutch
hydraulic linkage if bushing is worn or damaged.
(11) Verify that cap on clutch master cylinder res-
ervoir is tight. This will avoid spillage during
removal.
(12) Remove the nuts holding the clutch master
cylinder to the dash panel.
(13) Remove screws that attach clutch fluid reser-
voir to dash panel.
(14) Remove the clutch master cylinder from the
dash panel.
(15) Remove clutch cylinders, reservoir and con-
necting lines from vehicle.
INSTALLATION
The factory installed hydraulic linkage has a quick
disconnect at the slave cylinder. This fitting should
not be disconnected or tampered with. The hydraulic
linkage is serviced as an assembly only, but it comes
as two pieces to ease installation. Once the clutch
hydraulic line is connected to the slave cylinder, it
Fig. 35 Clutch Hydraulic Linkage
1 - DASH PANEL
2 - CYLINDER RESERVOIR
3 - CLUTCH MASTER CYLINDER
4 - SLAVE CYLINDER
5 - CLUTCH HYDRAULIC LINE
6 - 20 CLUTCHBR/BE
LINKAGE (Continued)
Page 334 of 2889

should not be disconnected. The individual compo-
nents that form the linkage assembly cannot be over-
hauled or serviced separately.
(1) Tighten cap on clutch fluid reservoir to avoid
spillage during installation.
(2) Position cylinders, connecting lines and reser-
voir in vehicle engine compartment. Locate the clutch
hydraulic line against the dash panel and behind all
engine hoses and wiring.
(3) Insert clutch master cylinder in dash panel.
Install and tighten the nuts to hold the clutch master
cylinder to the dash panel.
(4) Apply a light coating of grease to the inside
and outside diameter of the master cylinder bushing.
(5) Install clutch master cylinder push rod on
clutch pedal pin. Secure rod with retaining clip.
(6) Connect clutch pedal position (interlock) switch
wires.(7) Position clutch fluid reservoir on dash panel
and install reservoir screws. Tighten screws to 5 N´m
(40 in. lbs.) torque.
(8) Install the plastic clip securing the hydraulic
line to the dash panel into the lower dash panel
flange.
(9) Install the plastic clip securing the hydraulic
line to the dash panel onto the upper dash panel
stud.
(10) Raise vehicle.
(11) Install slave cylinder. Be sure cap at end of
cylinder rod is seated in release lever. Check this
before installing cylinder attaching nuts.
NOTE: If new linkage is being installed, do not
remove the plastic shipping strap from slave cylin-
der push rod. The shipping strap will break on its
own upon the first clutch application.
(12) Install and tighten slave cylinder attaching
nuts to 23 N´m (200 in. lbs.) torque.
(13) If a new clutch linkage is being installed, con-
nect the clutch hydraulic line (Fig. 37) to the clutch
slave cylinder.
(14) Lower vehicle.
(15) Operate linkage several times to verify proper
operation.
Fig. 36 Clutch Cylinder Push Rod Attachment
1 - PIN
2 - CLUTCH INTERLOCK WIRE
3 - PUSH ROD
4 - CLIP
Fig. 37 Clutch Slave Cylinder
1 - CLUTCH HYDRAULIC LINE
2 - CLUTCH SLAVE CYLINDER
BR/BECLUTCH 6 - 21
LINKAGE (Continued)
Page 335 of 2889
CLUTCH PEDAL POSITION
SWITCH
DESCRIPTION
A clutch pedal position (interlock) switch is in the
starter relay circuit and is mounted on the clutch
master cylinder push rod (Fig. 38). The switch is
actuated by clutch pedal movement.
OPERATION
The switch, which is in circuit with the starter
solenoid, requires that the clutch pedal be fully
depressed in order to start the engine. Switch cir-
cuitry and operation is provided in section 8W of
Group 8.
The position switch is an integral part of the clutch
master cylinder push rod and is not serviced
separately.
Fig. 38 Clutch Pedal Position (Interlock) Switch
1 - PIN
2 - CLUTCH INTERLOCK WIRE
3 - PUSH ROD
4 - CLIP
6 - 22 CLUTCHBR/BE
Page 336 of 2889

COOLING
TABLE OF CONTENTS
page page
COOLING
DESCRIPTION............................1
OPERATION.............................2
DIAGNOSIS AND TESTING..................4
PRELIMINARY CHECKS...................4
ON-BOARD DIAGNOSTICS (OBD)...........4
COOLING SYSTEM LEAKS................5
COOLING SYSTEM GAS ENGINE...........7
COOLING SYSTEM DIESEL ENGINE........12
STANDARD PROCEDURE..................15
DRAINING COOLING SYSTEM - 3.9L/5.2L/
5.9L/8.0L ENGINES......................15
DRAINING COOLING SYSTEM - 5.9L
DIESEL ENGINE........................15REFILLING COOLING SYSTEM - 3.9L/5.2L/
5.9L/8.0L ENGINES......................15
REFILLING COOLING SYSTEM - 5.9L
DIESEL ENGINE........................15
ADDING ADDITIONAL COOLANT...........16
COOLANT LEVEL CHECK................16
COOLING SYSTEM CLEANING/REVERSE
FLUSHING............................16
COOLANT SELECTION-ADDITIVES.........17
SPECIFICATIONS........................17
SPECIAL TOOLS.........................18
ACCESSORY DRIVE......................19
ENGINE................................39
TRANSMISSION.........................79
COOLING
DESCRIPTIONÐCOOLING SYSTEM FLOW -
3.9L/5.2L/5.9L ENGINE
The cooling system regulates engine operating tem-
perature. It allows the engine to reach normal oper-
ating temperature as quickly as possible. It also
maintains normal operating temperature and pre-
vents overheating.
The cooling system also provides a means of heat-
ing the passenger compartment and cooling the auto-
matic transmission fluid (if equipped). The cooling
system is pressurized and uses a centrifugal water
pump to circulate coolant throughout the system.
An optional factory installed maximum duty cool-
ing package is available on most models. This pack-
age will provide additional cooling capacity forvehicles used under extreme conditions such as
trailer towing in high ambient temperatures (Fig. 1).
DESCRIPTIONÐCOOLING SYSTEM FLOW -
5.9L DIESEL
The diesel engine cooling system consists of (Fig.
2):
²Cross-flow radiator
²Belt driven water pump
²Belt driven mechanical cooling fan
²Thermal viscous fan drive
²Fan shroud
²Radiator pressure cap
²Vertically mounted thermostat
²Coolant reserve/recovery system
²Transmission oil cooler
²Coolant
BR/BECOOLING 7 - 1