The clutch mechanism consists of a flywheel, a single,
dry-type disc, and a diaphragm style clutch cover. A
hydraulic linkage is used to operate the clutch release
bearing. The flywheel is bolted to the rear flange of
the crankshaft. The clutch cover is bolted to the fly-
wheel with the clutch disc located between these two
components. The clutch system provides a mechanical
link between the engine and the transmission. The
system is designed to ensure that the full torque out-
put of the engine is transferred to the transmission
while isolating the transmission from the engine firing
pulses to minimize concerns such as gear rattle.

CLUTCH

6 - 1

OPERATION

The clutch operates with leverage, clamping force, and friction. The disc serves as the friction element, the dia-
phragm-style clutch cover provides the clamping force. The clutch pedal, hydraulic linkage, and the release bearing
provide the leverage.

A shared reservoir for the brake system and clutch system is mounted to the dash panel. The clutch master cylinder
push rod is connected to the clutch pedal. When the clutch pedal is depressed, the slave cylinder is operated by the
clutch master cylinder mounted on the pedal assembly. The release bearing then depresses the clutch cover spring
fingers, thereby releasing pressure on the clutch disc and allowing the engine crankshaft to spin independently of
the transmission input shaft.

WARNING

WARNING: EXERCISE CARE WHEN SERVICING CLUTCH COMPONENTS. FACTORY INSTALLED CLUTCH
DISCS DO NOT CONTAIN ASBESTOS FIBERS. DUST AND DIRT ON CLUTCH PARTS MAY CONTAIN ASBES-
TOS FIBERS FROM AFTERMARKET COMPONENTS. BREATHING EXCESSIVE CONCENTRATIONS OF THESE
FIBERS CAN CAUSE SERIOUS BODILY HARM. WEAR A RESPIRATOR DURING SERVICE AND NEVER
CLEAN CLUTCH COMPONENTS WITH COMPRESSED AIR OR WITH A DRY BRUSH. EITHER CLEAN THE
COMPONENTS WITH A WATER DAMPENED RAG OR USE A VACUUM CLEANER SPECIFICALLY DESIGNED
FOR REMOVING ASBESTOS FIBERS AND DUST. DO NOT CREATE DUST BY SANDING A CLUTCH DISC.
REPLACE THE DISC IF THE FRICTION MATERIAL IS DAMAGED OR CONTAMINATED. DISPOSE OF ALL
DUST AND DIRT CONTAINING ASBESTOS FIBERS IN SEALED BAGS OR CONTAINERS. THIS WILL HELP
MINIMIZE EXPOSURE TO YOURSELF AND TO OTHERS. FOLLOW ALL RECOMMENDED SAFETY PRAC-
TICES PRESCRIBED BY THE OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION (OSHA) AND THE
ENVIRONMENTAL PROTECTION AGENCY (EPA), FOR THE HANDLING AND DISPOSAL OF PRODUCTS CON-
TAINING ASBESTOS.

DIAGNOSIS AND TESTING

CLUTCH SYSTEM

Drive the vehicle at normal speeds. Shift the transmission through all gear ranges and observe clutch action. If the
clutch chatters, grabs, slips or does not release properly, remove and inspect the clutch components. If the problem
is noise or hard shifting, further diagnosis may be needed as the transmission or another driveline component may
be at fault.

CLUTCH CONTAMINATION

Fluid contamination is a frequent cause of clutch malfunctions. Oil, water or hydraulic clutch fluid on the clutch disc
and pressure plate surfaces will cause chatter, slip and grab. Inspect components for oil, hydraulic fluid or water/
road splash contamination.

Oil contamination indicates a leak at either the rear main seal or transmission input shaft. Hydraulic clutch fluid
leaks are usually from damaged slave cylinder seals. Heat buildup caused by slippage between the clutch cover,
disc and flywheel can bake the oil residue onto the components. The glaze-like residue ranges in color from amber
to black.

Road splash contamination is dirt/water entering the clutch housing due to loose bolts, housing cracks. Driving
through deep water puddles can force water/road splash into the housing through such openings.

IMPROPER RELEASE OR IMPROPER CLUTCH ENGAGEMENT

Clutch release or engagement problems are caused by wear or damaged clutch components. A visual inspection of
the release components will usually reveal the problem component.

Release problems can result in hard shifting and noise. Look for leaks at the clutch hydraulic cylinders and inter-
connecting line. Also worn/loose clutch disc, clutch cover or release bearing.

Engagement problems can result in slip, chatter/shudder and noisy operation. The causes may be clutch disc con-
tamination, wear, distortion or flywheel damage. Visually inspect to determine the actual cause of the problem.

6 - 2

CLUTCH

CLUTCH MISALIGNMENT

Clutch components must be in proper alignment with the crankshaft and transmission input shaft. Misalignment
caused by excessive runout or warpage of any clutch component will cause grab, chatter and improper clutch
release.

CLUTCH COVER AND DISC RUNOUT

Check the clutch disc before installation. Axial (face) runout of a new disc should not exceed 0.50 mm (0.020 in.).
Measure runout about 6 mm (1/4 in.) from the outer edge of the disc facing. Obtain another disc if runout is exces-
sive.

Check condition of the clutch before installation. A warped cover or diaphragm spring will cause grab and incom-
plete release or engagement. Be careful when handling the cover and disc. Impact can distort the cover, diaphragm
spring, release fingers and the hub of the clutch disc.

Use an alignment tool when positioning the disc on the flywheel. The tool prevents accidental misalignment which
could result in cover distortion and disc damage.

A frequent cause of clutch cover distortion (and subsequent misalignment) is improper bolt tightening.

FLYWHEEL RUNOUT

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.

Common causes of runout are:

•

Heat warpage

•

Improper machining

•

Incorrect bolt tightening

•

Improper seating on crankshaft flange shoulder

•

Foreign material on crankshaft flange

Flywheel machining is not recommended. The flywheel clutch surface is machined to a unique contour and machin-
ing will negate this feature. 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 is not recommended. Replace the flywheel if scoring is severe and deeper than 0.076 mm (0.003 in.).
Excessive stock removal can result in flywheel cracking or warpage after installation; it can also weaken the fly-
wheel and interfere with proper clutch release.

Clean the crankshaft flange before mounting the flywheel. Dirt and grease on the flange surface may cause exces-
sive runout. Use new bolts when remounting a flywheel and secure the bolts with Mopar Lock And Seal or equiv-
alent. Tighten flywheel bolts to specified torque only. Overtightening can distort the flywheel hub causing runout.

CLUTCH

6 - 3

DIAGNOSIS CHART

The diagnosis chart describes common clutch problems, causes and correction. Conditions, causes and corrective
action are outlined in the indicated columns.

CONDITION

POSSIBLE CAUSES

CORRECTION

DISC FACING WORN OUT

1. Normal wear.

1. Replace cover and disc.

2. Driver frequently rides (slips) the
clutch. Results in rapid overheating
and wear.

2. Replace cover and disc.

3. Insufficient clutch cover
diaphragm spring tension.

3. Replace cover and disc.

CLUTCH DISC FACING
CONTAMINATED WITH OIL,
GREASE, OR HYDRAULIC
CLUTCH FLUID.

1. Leak at rear main engine seal or
transmission input shaft seal.

1. Replace appropriate seal.

2. Excessive amount of grease
applied to the input shaft splines.

2. Remove grease and apply the
correct amount of grease.

3. Road splash, water entering
housing.

3. Replace clutch disc. Clean clutch
cover and reuse if in good condition.

4. Slave cylinder leaking.

4. Replace hydraulic slave cylinder.

CLUTCH IS RUNNING PARTIALLY
DISENGAGED.

1. Release bearing sticking or
binding and does not return to the
normal running position.

1. Verify failure. Replace the release
bearing/slave cylinder and
transmission front bearing retainer
as necessary.

FLYWHEEL BELOW MINIMUM
THICKNESS SPECIFICATION.

1. Improper flywheel machining.
Flywheel has excessive taper or
excessive material removal.

1. Replace flywheel.

CLUTCH DISC, COVER AND/OR
DIAPHRAGM SPRING WARPED
OR DISTORTED.

1. Rough handling. Impact bent
cover, spring, or disc.

1. Replace disc or cover as
necessary.

2. Improper bolt tightening
procedure.

2. Tighten clutch cover using proper
procedure.

FACING ON FLYWHEEL SIDE OF
DISC TORN, GOUGED, OR
WORN.

1. Flywheel surface scored or
nicked.

1. Correct surface condition if
possible. Replace flywheel and disc
as necessary.

2. Clutch disc sticking or binding on
transmission input shaft.

2. Lubricate splines with high
temperature grease.

CLUTCH DISC FACING BURNT.
FLYWHEEL AND COVER
PRESSURE PLATE SURFACES
HEAVILY GLAZED.

1. Frequent operation under high
loads or hard acceleration
conditions.

1. Correct condition of flywheel and
pressure plate surface. Replace
clutch cover and disc. Alert driver to
problem cause.

2. Driver frequently rides (slips)
clutch. Results in rapid wear and
overheating of disc and cover.

2. Correct condition of flywheel and
pressure plate surface. Replace
clutch cover and disc. Alert driver to
problem cause.

6 - 4

CLUTCH

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