Re post 17331, well spotted Jai, it was indeed the drop arm ball joint. It had lost its circlip, end cap and spring. Fairly cheap repair. In fact it cost me nothing, because as a temporary measure I swiped the bits off my friend's Land Rover. It's on SORN at the moment. I wil tell him when he gets back (I won't just let him think his has fallen out!), and buy us both new kits when I get back to civilisation. Where I am here it's a 40 mile trip to the nearest legitimate source of parts (and that's a main stealer), so it's bushcraft repairs for us!