I'm not sure what broke, but something else caused this. A couple weeks ago a some friends borrowed my truck to pull one of theirs back home after they broke. When they brought it back the front d-shaft had the busted joint shown here. I fixed it today and went out to play in the snow, now I got no 4wd. The front shaft spins but the axles don't. I suspect its a broken axle inside the shaft, sice both axle joints are intact but neither axle spins when given power. Anybody seen a u-joint break like that? The joint was whatever brand O' Reilly sells( I was in a pinch when I bought it) and is less than 6 months old. The big chunk of joint was still in the yoke as seen in the picture, the shaft looks exactly the same as when they brought it home. What would cause it to break like that before an axle joint gave out? Must have been in a real bind.