Hi was wondering if anyone could help,just bought a freelander 2000 plate,starts fine and engine fine,when you take off thers this big thumping noise going right threw the lander,starts from the back somewere,when i increase the speed it dies down but still ther,when i slow down the thumping gets louder again,thers a service light on picture of lander pointing to like 7 0clock,anyone any idea.cheers