Hi, We have the same issue with the Land Rover. Changed literally everything (changed front and back bushes, cardan shaft, A frame bushes, wheel alignment, and others) but we still haven't figured out the problem.
When it is at 1st gear and start to drive, a loud thud will come from the back and at like 40/50mph the land rover starts to vibrate alot.
The steering does not wobble though it just vibrates with the whole body. Did a wheel balance but when braking it goes to the drivers side (right hand side).
Also, recently we noticed that there is a noise like a pulley or something.... Can someone help us please because we are coming to a dead end?