Clonk from diff when on/off power

[273lbft]

Hi there

I have a 1995 LS400. I've just joined but it's not the first time I've been on here - a post on here saved me when my alarm started to go berserk after reinstalling the Battery, so thanks for that!

I have a long-standing problem, which is that when on and off the power remotely sharply, as well as when putting it into D, there is a very audible 'clonk' from the rear diff. If you properly jump on the throttle it feels so harsh it makes me wince. You can feel as well as hear it. I had a look underneath and the diff mount looks tired but not necessarily utterly perished. I asked my garage to take a look at MOT time and they replaced the transmission and diff oil, which alleviated the symptoms ever so slightly, but it is still very much there.

Does anybody have any ideas? It is most definitely from the rear so I am ruling out engine mounts etc. It's done 120k and has mostly lived in London, perhaps it's the start/stop traffic and/or speed bumps?

Many thanks in advance

J

[NemesisUK]

Worn or maladjusted crown wheel thrust bearing?

Worn propshaft centre bearing?

[Tinonline]

I’d be a bit surprised if it is the diff. Plenty of rubber bushes or UJ worn more like. Not always easy to detect.