If the rear transmission mount on my 745t was bad would a hollow knocking sound be made when going over certain bumps? I can pull the rear of the transmission down, hear a knock and see metal to metal to metal contact between the trans and the cross member. Can I be fairly certain that this is the cause of the hollow knocking noise? Has anybody experienced or know of similar situations. Also, should I be able to move the drive shaft around in the center\mid drive shaft bushing\support enough to make clunking noises? Any help, comments, observations would be appreciated.