if its a 300tdi discovery as in your sig, scraw under and attatched to the diff at the rear, between the prop and diff theres a rubber coupling, to cushion gearchanges, but it was a crud idea and just makes them jerk if not careful when gearchanges, also if crawling in 1st gear then you take off or back off the throttle then hit it again, it kangaroo's like mad
every 300 disco that ive drove or been a passenger in does it, mine has got new suspention and bushes all round so theres nowt rong with that....so it eliminated suspention, btw mine box standard aswel
dan