here is some pics of the one that i just broke.  this break was less catasrophic than past breakage i have had.  the last one i ended up breaking both the inner and outer shaft into about four pieces each.  i have never broken a u-joint though.  i think the weak area is the narrow edges that wrap around the u-joint.  thats what broke this time. the other thing that sucks is when they do break, the snap rings and bearing caps get all chewed up and get stuck inside the knuckle when you turn it.  the inside of my knuckle is all beat to hell from those axles.