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.
NOTE: Vehicles equipped with a Dual Mass Flywheel may produce a rattle when the engine is shut off. This noise is considered normal.
Fluid contamination is a frequent cause of clutch malfunctions. Oil, water or 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. Clutch fluid leaks are usually from damaged slave cylinder push rod seals. Heat buildup caused by slippage between the pressure plate, 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.
Clutch release or engagement problems are caused by wear or damage clutch components. A visual inspection of the release components will usually reveal the problem part.
Release problems can result in hard shifting and noise. Look for leaks at the clutch cylinders and interconnecting line and loose slave cylinder bolts. Also worn/loose release fork, pivot stud, clutch disc, pressure plate or release bearing.
Engagement problems can result in slip, chatter/shudder and noisy operation. The causes may be clutch disc contamination, wear, distortion or flywheel damage. Visually inspect to determine the actual cause of the problem.
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.
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 excessive.
Check condition of the clutch before installation. A warped cover or diaphragm spring will cause grab and incomplete 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 consequent misalignment) is improper bolt tightening.
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 flywheel bolts.
Common causes of runout are:
Flywheel machining is not recommended. The flywheel clutch surface is machined to a unique contour and machining 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 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 Mopar Lock And Seal or equivalent. Tighten flywheel bolts to specified torque only. Overtightening can distort the flywheel hub causing runout.
The diagnosis charts Diagnosis Chart describe 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 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 clutch linkage. |
|
|
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 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. |
|
|
3. Contamination of clutch. |
3. Correct fluid leak. Replace clutch cover and disc. |
|
|
Clutch disc binds on input shaft splines. |
1. Clutch disc hub splines damaged during installation. |
1. Clean, smooth, and lubricate hub splines if possible. Replace disc if necessary. |
|
2. Input shaft splines rough, damaged, or corroded. |
2. Clean, smooth, and lubricate shaft splines if possible. Replace input shaft if necessary. |
|
|
Clutch disc rusted to flywheel and/or pressure plate. |
1. Clutch not used for and extended period of time (e.g. long term vehicle storage). |
1. Sand rusted surfaces with 180 grit sanding paper. Replace clutch cover and flywheel if necessary. |
|
Pilot bearing seized, loose, or rollers are worn. |
1. Bearing cocked during installation. |
1. Install and lubricate a new bearing. |
|
2. Bearing defective. |
2. Install and lubricate a new bearing. |
|
|
3. Bearing not lubricated. |
3. Install and lubricate a new bearing. |
|
|
4. Clutch misalignment. |
4. Inspect clutch and correct as necessary. Install and lubricate a new bearing. |
|
|
Clutch will not disengage properly. |
1. Low clutch fluid level. |
1. Replace hydraulic linkage assembly. |
|
2. Clutch cover loose. |
2. Follow proper bolt tightening procedure. |
|
|
3. Clutch disc bent or distorted. |
3. Replace clutch disc. |
|
|
4. Clutch cover diaphragm spring bent or warped. |
4. Replace clutch cover. |
|
|
5. Clutch disc installed backwards. |
5. Remove and install clutch disc correctly. |
|
|
6. Release fork bent or fork pivot loose or damaged. |
6. Replace fork or pivot as necessary. |
|
|
7. Clutch master or slave cylinder failure. |
7. Replace hydraulic linkage assembly. |
|
|
Clutch pedal squeak. |
1. Pivot pin loose. |
1. Tighten pivot pin if possible. Replace clutch pedal if necessary. |
|
2. Master cylinder bushing not lubricated. |
2. Lubricate master cylinder bushing. |
|
|
3. Pedal bushings worn out or cracked. |
3. Replace and lubricate bushings. |
|
|
Clutch master or slave cylinder plunger dragging and\or binding |
1. Master or slave cylinder components worn or corroded. |
1. Replace clutch hydraulic linkage assembly. |
|
Release bearing is noisy. |
1. Release bearing defective or damaged. |
1. Replace release bearing. |
|
Contact surface of release bearing damaged. |
1. Clutch cover incorrect or release fingers bent or distorted. |
1. Replace clutch cover and release bearing. |
|
2. Release bearing defective or damaged. |
2. Replace the release bearing. |
|
|
3. Release bearing misaligned. |
3. Check and correct runout of clutch components. Check front bearing sleeve for damage/alignment. Repair as necessary. |
|
|
Partial engagement of clutch disc. One side of disc is worn and the other side is glazed and lightly worn. |
1. Clutch pressure plate position incorrect. |
1. Replace clutch disc and cover. |
|
2. Clutch cover, spring, or release fingers bent or distorted. |
2. Replace clutch disc and cover. |
|
|
3. Clutch disc damaged or distorted. |
2. Replace clutch disc. |
|
|
4. Clutch misalignment. |
4. Check alignment and runout of flywheel, disc, pressure plate, and\or clutch housing. Correct as necessary. |