Since i put my car back together, the center where my tranmission and driveshaft are make a loud noise like if something is bangin up and it makes it worse when i go in reverse and it also whines when it goes in reverse. The tranny fluid is full and since i was under my car the(with the two front wheels in the air and the back ones on the ground) the driveshaft seems to have some play in it? All the bolts are tight but it sounds like something is loos. Has this ever happen to anybody? Hope someone can help.