I kicked a driveshaft out of my 67 Barracuda once. I had just swapped the 3rd member and used a new set of u-joint straps. Turned out they were for the larger joint. They bolted on fine, but they did not stretch down over the caps, they fit flush without bolts. I didn't notice and used them. I took off down the road and up around 70mph my driver door started to vibrate. I thought to myself, "that's odd, never done that before", just then KABAAAMMM...thumpeta..thumpetaaaa. That sucked. Had the driveshaft repaired,installed with new correct straps, hammered the floor back down (big dent on rear seat footwell tunnel)and hit the road. After that it had a tiny vibe in the upper MPHs. A couple of months later I found out what the vibe was. I pulled off the freeway on a lonely offramp heading for my friends house and while gently pulling away from the stop sign, click, tink tink tink.. Looked under the car and there is the driveshaft on the ground with the yoke and half of the pinion still attached
I'm glad that didn't happen moments before as I was playing with a Camaro at 100+mph. Appearently the original driveshaft pop-out episode caused a fracture in the pinion and it finally gave way. I am 100% certain on what straps I use on u-joints now. That learning curve nearly had a u-turn in it.
Travis..