It's very intermittent, car is an auto and has so far had...
November
STRIP OUT TO REMOVE REAR DIFFERENTIAL FOR PINION BEARING KIT REPLACEMENT.
REFIT REAR DIFFERENTIAL, REPLACED ALL OILS.
ROAD TESTED WITH NO NOISE FROM THE REAR DIFFERENTIAL, RETURN CAR TO CUSTOMER.
August
CARRY OUT MOT TEST
CARRY OUT INSPECTION SERVICE
REMOVE PROP SHAFT AND SEND AWAY FOR SPECIALIST REPAIR
RE-FIT REFURBISHED PROP SHAFT AND TEST, ALL OK