clunking from back end chassis area when going over sharp little bumps etc..??

hi everyone. just to clarify with this one...
shes a 1989 Td 90 and recently just started hearing from the back end alot of clanking and like a metal on metal bag of bones kinda thing.. but i only get this when going over ruff ground or sharp lil ruts and cracks in the road etc.. now i don't get this when changing gear; or if i stand on the wheel and shake the whole cab... now what do you recon this could be, worn bushes, dampers?? or is worse and the cabs gonna fly off the chassis at some point!? ..
any help on what i need to do, cheers..

shockers ,maybe rollbar bushes if fitted

A frame ball joint

the bottom bushes on my shockers were really worn a while back, every time i went over a bump the plates were hitting off each other, clunking, id deffo check the shocker bushes..

I'm with Daft. A frame ball joint.

A frame ball joint - I think Busterbus has a guide for replacing them.

cheers guys, had a good luck around underneath, def sure the bushes are warn (SPLIT AND WAFER THIN) not entirely sure what they call those bushes tho, when ordering??
gonna replace the A frame ball joint too, it looks abit old and rusty.. probs got something to do with the nocking too..

a frame ball joint gives a knock when setting off or during gear change when torque applied to axle trys to rotate it,do your shockers first not allways the bushes ,sometimes the shockers themselves,then A frame if necessary ,not nice to do for the sake of it