Got a bit of a Jeep run this weekend. Probably going to be about 150 miles of touring the fall leaves. Last night I decided to check on my front driveshaft - last time I drove it, the Jeep felt like it was getting front driveline vibrations (in addition to the rear :S ) The U Joints are new, Cardan centering ball was recently regreased so I wasn't thinking anything would be wrong. Either way, felt like I should check. Rolled under the Jeep (nice thing about a lifted Jeep!) and go to wiggle the shaft. Lots of play in it. Turns out the slip yoke had failed. Pulled the driveshaft out to assess the situation. It would wiggle side to side and it seemed that the splines were wore out and there was a bit of slop (like transmitting power) in it as well. At this point, I decided to go into the bathroom. That's where I keep my spare driveshafts and axleshafts. Started to take a look at my spare driveshafts and found one that was the correct length. Took me a while, but I pressed the bad one apart, used the cardan yoke and the new u joints, put them on the other driveshaft and we're back in business! So being a parts hoarder and keeping stuff in your bathroom is not a bad thing! ...but probably why I'm single.