Bad wheel bearings?
 

I'm having a vibration problem but it continues to do it out of gear too.......usually a lower speeds.
Sometimes I hear some clicking sounds but it doesn't last long.
I'm thinking that since it does it out of gear that maybe it could be a bad wheel bearing.
How do you check for a bad wheel bearing and U-joints?
I replaced one U-loint last year but I don't remember which one.

One way would be to just grab the wheel and see if you can wiggle it back and forth. If you have too much play in it, it is probably the bearings. They may be bad or they may just need to be re-packed.