It's all polybushed James, the mounts and the arms, I know the mounts are ok to polybush, it just seems to vibrate a lot more than my old sapph used to under acceleration, my sapph went from standard beam with standard bushes to an adjustable beam with rose joint inner and outers on the arms and was always fine. Just wondered if this is one of the problems you get with polybushed rear arms?

Karl