I know exactly what you are talking about. I am pretty sure that it is simply because of the one piece shaft. I once replaced my center support bearing and neglected to put these two little spacers back in during instal. It was horrible. making a metal on metal rubing sound and gets worse the faster that you go??? I lost the spacers so I went to Home Depot to just pick some up. I put those on and the same thing happen only a little different sound. I found out that it was because those spacers were too thick. If they are not just right, then the U joint that sits right there at the tranny entrance rubs on that cover. I suggest for you to just get some dikes on take it off. Hope I helped you out.,