ok this is good, we can start eliminating some of the areas. its not the leaves as I just had mine changed, problem was there before and after suspension change. I doubt its the tub itself. when my ute was a week old there was a massive thump from the tub. took it to dealer, the tub was loose, all fixed now. very different sound to what I hear now. its more of a metal on metal rattle like others describe rather than a thump. I have only developed this rattle in the last 3 months or so @ 40,000km more?