My Nissan had a CV joint go bad. It went from no symptoms to unsafe to drive in a week. Not a problem, I've changed axles before without much trouble. Got it apart, put the new axle in, put the steering parts back on with minimal hassle. Except when I went to drive, the car didn't move. The axle went in far enough to put stuff back together, but not far enough to actually connect to the transmission.
No matter how I beat on it, no luck. We needed another car anyhow, and I found a decent deal on a low-miles 97 Cavalier:
(It originally had a window sticker that said "Badass girls drive badass toys". It is a stock Cavalier with an automatic. Someone's idea of badass is a bit different than mine)
Anyhow--I bought a bigger hammer, and still had no luck with the Nissan axle, so I found someone who would come to my house and do the work.
Turns out the axle was defective--The splines were mushroomed into the slots, so the splines inside couldn't get in. I got the replacement axle, and the guy I hired popped it in with no trouble--If the first one had been correct, I would have had the car back on the road that day. I hate stuff like that, it makes me feel incompetent--I should have spotted the problem.