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ost_uid0]How about the whole exhaust moving around. I know mine does. Just wriggles a bit over short chattery bumps and the noise that I get is on the rear left not the right so that doesn't help a whole lot. Spare wheel? Rear window washer bottle? I'm just clutching at straws here. Maybe a nut fallen from the boot under the rear seat? Sex aid?
Also get a clunk from the towbar shackle jumping up and down over really small sharp bumps but I don't imagine you'd have that problem.
Maybe your suspension bushes are worn?
Hope this gives you some ideas. Except for the sex aid bit
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