Hello again!! I just got a new work truck (well new to me) and it is making a goofy noise that sounds like its coming from the drive shaft support (according to my neighbor who stood beside the truck to listen too it). The truck is an 09 3500 6.7L with 2wd 6 speed manual. When I take do a normal take off in reverse there is a clunking noise when the clutch is let out. When I go to stop it (still in reverse) I hear the same thing when the clutch is put in. The only time it does not do this is when I Let in or out of the clutch slowly. Some times it does this in first gear as well but none of the other gears have this problem. It does however have a vibration that is very noticeable starting at 65mph and up. I know the truck has a brand new clutch and I am not feeling anything in the clutch pedal. I crawled under the truck and twisted on the Rear portion of the drive shaft while holding the front still and there was some give there. Also I pushed up and down on the drive shaft and it moved up and down about 1/4" each way inside the rubber piece on the center support. I am wording if my neighbor is correct on what he heard. I have never had this problem before so I have not a clue what to look for.

Thanks All!