Transfer case noise when in Reverse with brake on

[hyrific]

Ok I replaced the U joints because its not too hard and cheap. one of them did have some play. Problem is the T-Case still makes the rattle. I can feel the rattle when I touch the T-Case. The T-case now makes the rattle when I am in park and the engine is revved up at 2000 rpm. What would be moving around in the T-Case in park? When I am in park does the transmission spin the T-case in any way? 4WD does work.