Rubber pads are standard on the 49 but when I put my bed wood in I forgot (or didn't know) about them. The wood blocks are in good condition and bolted down tight. On the rear the bed is bolted to a steel "block" instead of wood. I do not have rubber pads in that place and now I am narrowing this problem down to possibly this. I have the impression that as long as the bed is tight it should not thump but maybe the metal on metal in the rear is doing it.
Tell you if I ever find the answer to this there will be one heck of a party and you are all invited!
