This JUST started happening today. Drove my truck to work today and had no issues, went to lunch still no issues. Get in to go home and I get on the freeway and up to speed, all the sudden a noticeable vibration/rattle/shudder started.
Not sure what it is, thought maybe the engine but when I stopped at the next gas station I put it in park and revved the RPMs up and didnt feel any shaking or vibration so I dont think it is a misfire.
Any ideas as to what it could be?

 

Moved to correct section

 

Sorry wasnt sure where to post it, anyone have any ideas?

 

u-joint