Noisy in neutral with engine running - Input shaft bearings worn (noise apparent with clutch pedal released, but not when depressed) - Clutch release bearing worn (noise apparent with clutch pedal depressed, possibly less when released)

Noisy in one particular gear

- Worn, damaged or chipped gear teeth

Difficulty engaging gears

- Clutch fault
- Worn or damaged gear-change linkage/cable
- Incorrectly-adjusted gear-change linkage/cable
- Worn synchronizer units

Jumps out of gear

- Worn or damaged gear-change linkage/cable
- Incorrectly-adjusted gear-change linkage/cable
- Worn synchronizer units
- Worn selector forks

Vibration

- Lack of oil
- Worn bearings

Lubricant leaks

- Leaking differential output oil seal
- Leaking housing joint
- Leaking input shaft oil seal