Do you get any unusual noises when engaging drive after turning a corner or when you reberse round a bend ?
My wifes car (MY02 TD4) had a slight judder on pull off and made a clunk from the rear when turning a corner and then engaging 2nd gear on pull away, this proved to be the top Diff mount at the rear.
I have just had it done today and the car is perfect again, ohh the part was £10ish from LR but was fitted under warranty by my dealer in about 1/2 an hour.
Zippy