axle u joint and axle shaft
 

I have a axle u joint that is failing. Its been going out for a while. I was reading about the ems free spin kit on their site and they mention the axle shaft going bad when the u joint goes. Does this happen often? How can I tell if mine is bad?

Probably not bad unless you let it go for a long time or didnt notice it to the point where the ujoint is practically gone and its been bangin around in there and the shafts ends are all beat up