what is axle wrap? does this cause you to eat up u joints. this is the third one I've had to install. how much does it cost to have my (1 piece) drive shaft ballanced? Is it common for them to become out of ballance? Especially when your u-joint falls appart and your axle develops a lot of slop in the rear joint as a result? This is the rear driveshaft I'm talking about. about every 2 months it (the rear u-joint) starts chirping and vibrating like crazy untill I replace it. When I pull the old one out it feels like it's bound up some how, almost impossible to move.