Found this with lots of comments below it from fellow sufferers. Looks like the whole axle shakes from side to side rather than just the steering making me think it’s bushings and panhard rod mountings though I’ve no experience of this myself. While I’m putting this up just for the visual aspect, the thing I’ve noticed is in the underneath shot, there seems to be no trailing arm in the front bracket on the axle in the right of the picture. It appears that the bolt is visible. It doesn’t make sense to me but if it’s the case then no wonder the thing is shaking.