Rear knock when turning

[Jamturbo]

Hi
I am experiencing a knock from the rear which I think I hear on both sides depending on the direction I am turning. What might be the first thing to check?
Thanks

 

[mmm-five]

Body (or something else) loose in the boot?

 

[Special Kay]

Sounds very homo erotic

 

[bigwinn]

How are your drop links

If one has snapped that can make an annoying noise