Knocking, clunk noise from diff ? rear end somewhere HELP

[Shiz]

Hi guys, I noticed this last year, but essentially if I was to give the right foot plenty at junctions, you would hear this almight thud, like a clunking noise from the diff.. I heard it last year before she went in for hibernation, but its really annoying me now. Its a 318i 1990. I have a feeling there is an lsd in it, or a very good open diff. The noise almost feels like its locking the diff with an almight bang. Then saying that I notice it sometimes changing through the gears. I am aware there is bearings, and possible bushions at the rear. But does this problem sound like anything obvious. Advice and help much appreciated asap guys. Thanks

[Speedtouch]

Could also be loose propshaft, or even wheel bolts, or a worn out propshaft guibo.

[magpie]

check the x4 bolts that holt the diff to the beam are tight ,i've seen these work loose before causing the diff to clonk about .