The mechanic moved one of the tires to the front, he said it was worn unevenly-that was the drive wheel and its also out of round.

He checked everything top to bottom, I doubt he pulled the axles. But he did tell me the u joints didnt feel bad, they did have some stiffness, but not bad-so he said he "tweaked them".

My truck now doesnt vibrate as bad at speed and on take off the trasfercase shifter doesnt wiggle back and forth nearly as much as it did-but I can still feel it.

Thats why I am thinking:
A: I know my tires are out of round, I just didnt have the cash to buy the ones I wanted, toss up between Firestone Destinations or Michelin LTX or such.

AFAIK after trying to balance them with a mechanic at the shop I tow for: The tires are SEVERELY out round. So much so that they took multiple weights and were hard to do and still vibrate. I just didnt get new ones b/c I barely drive the truck atm b/c of my work truck/van/tow truck.

B: The U joints gotta be on thier way out, I figure int he next 6 months I may change them. But I wanna see what new tires do first. If I change them, and I still have issues I am pulling the axles to check, nothing else seems to be wrong and my mech spent 2 weeks and looked it over top to bottom.