I own a 2004 Land Rover Defender and am having problems with the clutch master cylinder. A leaking unit was changed a year ago and lasted only four months, so it was changed again and lasted six months. A new one was fitted this week and I am wondering how long this will last. The local garage has been very helpful and not charged for any of the replacements but have now told me that they can't do any more. They have however suggested I have the pedal bearings changed just in case something is out of line. Have you ever come across this sort of problem and if so what could be the cause?