Well, this weekend I took the big ole heavy Truck Blazer to the mud races just to be loud and throw some mud. Yesterday on my 2nd run, the front u-joint came loose... bent the u-bolt straps and the u-joint flew out of the yoke. I fixed it with my spare driveline, and made my last 2 runs just fine. Today I went to another one. Mud was thicker and deeper. Not even 20 feet in... same thing happened. One strap bent out and the u-joint flew out of the yoke. Ok, so I didn't think it would happen again. Luckily, someone gave me a used u-joint and I put that in the other driveline end I swapped out yesterday and slid that into place. Got about 40 feet in churning up some thick mud, all 4 spinning good, then up go the RPMs and I loose front wheel again. That makes 3 times in 2 days the same u-joint keeps flying out. Maybe something internal in the front end is catching and forcing a strap to bend and disintegrate the caps? Maybe the yoke got worn or screwed up from the first time it came apart? What do you think?