Rattling noise – A worn bearing can produce rattling noises. These noises are most noticeable when the clutch pedal is pressed down. 

Difficulty changing gears– If the bearing lacks proper lubrication, the clutch may not fully release, resulting in difficulty shifting gears.

Vibration in the pedal – A worn release / trust / throw out bearing can cause the clutch pedal to vibrate. This is due to the worn bearing being unable to distribute even pressure onto the clutch plate, causing uneven contact with the pressure plate.