Manufacturer’s Professional Repair Information for the “Car Savvy Do it Yourselfer” Over 90 years of  service.




NOTE: This is GENERAL information. This article is not intended to be specific to any unique situation or individual vehicle configuration. The purpose of this Troubleshooting information is to provide a list of common causes to problem symptoms. For model-specific Troubleshooting, refer to SUBJECT, DIAGNOSTIC, or TESTING articles available in the section(s) you are accessing.

Chattering or Grabbing
Incorrect clutch adjustment Adjust clutch
Oil, grease or glaze on facings Disassemble and clean or replace
Loose "U" joint flange See DRIVE AXLES article
Worn input shaft spline Replace input shaft
Binding pressure plate Replace pressure plate
Binding release lever See CLUTCH article
Binding clutch disc hub Replace clutch disc
Unequal pressure plate contact Replace worn/misaligned components
Loose/bent clutch disc Replace clutch disc
Incorrect transmission alignment Realign transmission
Worn pressure plate, disc or flywheel Replace damaged components
Broken or weak pressure springs Replace pressure plate
Sticking clutch pedal Lubricate clutch pedal & linkage
Incorrect clutch disc facing Replace clutch disc
Engine loose in chassis Tighten all mounting bolts
Failure to Release
Oil or grease on clutch facings Clean or replace clutch clutch disc
Incorrect release lever or pedal adjustment See CLUTCH article
Worn or broken clutch facings Replace clutch disc
Bent clutch disc or pressure plate Replace damaged components
Clutch disc hub binding on input shaft Clean or replace clutch disc and/or input shaft
Binding pilot bearing Replace pilot bearing
Sticking release bearing sleeve Replace release bearing and/or sleeve
Binding clutch cable See CLUTCH article
Defective clutch master Replace master cylinder
Defective clutch slave Replace slave cylinder
Air in hydraulic system Bleed hydraulic system
Weak or broken release lever spring Replace spring and check alignment
Damaged pressure plate Replace pressure plate
Broken clutch return spring Replace return spring
Worn splines on clutch disc or input shaft Replace clutch disc and/or input shaft
Worn clutch release bearing Replace release bearing
Dry or worn pilot bearing Lubricate or replace pilot bearing
Unequal release lever contact Align or replace release lever
Incorrect pedal free play Adjust free play
Warped or damaged clutch disc Replace damaged components
Pressure springs worn or Release pressure plate
Oily, greasy or worn facings Clean or replace clutch disc
Incorrect clutch alignment Realign clutch assembly
Warped clutch disc or pressure plate Replace damaged components
Binding release levers or clutch pedal Lubricate and/or replace release components
Worn or damaged release Replace release bearing
Dry or worn pilot or release bearing Lubricate or replace assembly
Pilot bearing turning in crankshaft Replace pilot bearing and/or crankshaft
Worn input shaft bearing Replace bearing and seal
Incorrect transmission alignment Realign transmission
Dry release fork between pivot Lubricate release fork and pivot
Heavy and/or Stiff Pedal
Sticking release bearing sleeve Replace release bearing and/or sleeve
Dry or binding clutch pedal hub Lubricate and align components
Floor mat interference with pedal Lay mat flat in proper area
Dry or binding ball/fork pivots Lubricate and align components
Faulty clutch cable Replace clutch cable
Noisy Clutch Pedal
Faulty interlock switch Replace interlock switch
Self-adjuster ratchet noise Lubricate or replace self-adjuster
Speed control interlock switch Lubricate or replace interlock switch
Clutch Pedal Sticks Down
Binding clutch cable See CLUTCH article
Springs weak in pressure plate Replace pressure plate
Binding in clutch linkage Lubricate and free linkage
Dry release bearing Lubricate or replace release bearing
Dry or worn pilot bearing Lubricate or replace bearing
Worn input shaft bearing Replace bearing
Transmission Click
Weak springs in pressure Replace pressure plate plate
Release fork loose on ball stud Replace release fork and/or ball stud
Oil on clutch disc damper Replace clutch disc
Broken spring in slave cylinder Replace slave cylinder


Unrelated Noises

Some driveline trouble symptoms are also common to the engine, transmission, wheel bearings, tires, and other parts of the vehicle. Ensure cause of trouble actually is in the drive axle before adjusting, repairing, or replacing any of its parts.

Non-Drive Axle Noises

A few conditions can sound just like drive axle noise and have to be considered in pre-diagnosis. The 4 most common noises are exhaust, tires, CV/universal joints and wheel trim rings.

In certain conditions, the pitch of the exhaust gases may e gear whine. At other times, it may be mistaken for a wheel bearing rumble.

Tires, especially radial and snow, can have a high-pitched tread whine or roar, similar to gear noise. Also, some non-standard tires with an unusual tread construction may emit a roar or whine.

Defective CV/universal joints may cause clicking noises or excessive driveline play that can be improperly diagnosed as drive axle problems.

Trim and moldings also can cause a whistling or whining noise. Ensure none of these components are causing the noise before disassembling the drive axle.

Gear Noise

A "howling" or "whining" noise from the ring and pinion gear can be caused by an improper gear pattern, gear damage, or improper bearing preload. It can occur at various speeds and driving conditions, or it can be continuous.

Before disassembling axle to diagnose and correct gear ke sure that tires, exhaust, and vehicle trim have been checked as possible causes.


This is a particular rattling noise that sounds like a stick against the spokes of a spinning bicycle wheel. It occurs while decelerating from 40 MPH and usually can be heard until vehicle comes to a complete stop. The frequency varies with the speed of the vehicle.

A chuckle that occurs on the driving phase is usually caused ive clearance due to differential gear wear, or by a damaged tooth on the coast side of the pinion or ring gear. Even a very small tooth nick or a ridge on the edge of a gear tooth is enough the cause the noise.

This condition can be corrected simply by cleaning the gear tooth nick or ridge with a small grinding wheel. If either gear is damaged or scored badly, the gear set must be replaced. If metal has broken loose, the carrier and housing must be cleaned to remove particles that could cause damage.


This is very similar to a chuckle, though it may be louder, and occur on acceleration or deceleration. Knock can be caused by a gear tooth that is damaged on the drive side of the ring and pinion gears. Ring gear bolts that are hitting the carrier casting can cause knock. Knock can also be due to excessive end play in the axle shafts.


Clunk is a metallic noise heard when an automatic transmission is engaged in Reverse or Drive, or when throttle is applied or released. It is caused by backlash somewhere in the driveline, but not necessarily in the axle. To determine whether driveline clunk is caused by the axle, check the total axle backlash as follows:

  1. Raise vehicle on a frame or twinpost hoist so that drive wheels are free. Clamp a bar between axle companion flange and a part of the frame or body so that flange cannot move.
  2. On conventional drive axles, lock the left wheel to keep it from turning. On all models, turn the right wheel slowly until it is felt to be in Drive condition. Hold a chalk marker on side of tire about 12" from center of wheel. Turn wheel in the opposite direction until it is again felt to be in Drive condition.
  3. Measure the length of the chalk mark, which is the total axle backlash. If backlash is one inch or less, drive axle is not the source of clunk noise.

Bearing Whine

Bearing whine is a high-pitched sound similar to a whistle. It is usually caused by malfunctioning pinion bearings. Pinion bearings operate at drive shaft speed. Roller wheel bearings may whine in a similar manner if they run completely dry of lubricant. Bearing noise will occur at all driving speeds. This distinguishes it from gear whine, which usually comes and goes as speed changes.

Bearing Rumble

Bearing rumble sounds like marbles being tumbled. It is usually caused by a malfunctioning wheel bearing. The lower pitch is because the wheel bearing turns at only about 1/3 of drive shaft speed.

Chatter On Turns

This is a condition where the entire front or rear of vehicle vibrates when vehicle is moving. The vibration is plainly felt as well as heard. Extra differential thrust washers installed during axle repair can cause a condition of partial lock-up that creates this chatter.

Axle Shaft Noise

Axle shaft noise is similar to gear noise and pinion bearing whine. Axle shaft bearing noise will normally distinguish itself from gear noise by occurring in all driving modes (Drive, cruise, coast and float), and will persist with transmission in Neutral while vehicle is moving at problem speed.

If vehicle displays this noise condition, remove suspect parts, replace wheel seals and install a new set of bearings. Re-evaluate vehicle for noise before removing any internal components.


Vibration is a high-frequency trembling, shaking or grinding condition (felt or heard) that may be constant or variable in level and can occur during the total operating speed range of the vehicle.

The types of vibrations that can be felt in the vehicle can d into 3 main groups:

  • Vibrations of various unbalanced rotating parts of the vehicle.
  • Resonance vibrations of the body and frame structures caused by rotating of unbalanced parts.
  • Tip-in moans of resonance vibrations from stressed engine or exhaust system mounts or driveline flexing modes.