My drive axle (passenger side) would not snap back in when I tried to put it back in. When I pulled the axle back, I saw that there was an oring type deal that was hanging down. I searched but this does not seem to be the axle snap seal. Just wondering what it is and if it's causing my axle not to snap back in.

 

bump please help

 

its a small round spring that sits on the backside of that axle seal, it keeps the seal with pressure on the axle so it doesnt leak, pop that seal out replace it with a new one ($12) and your good to go

 

That looks like a shim to me.