Vibrations 25 - 50 mph

I have a stock 2005 2.7 5 speed manual Tacoma with 130k miles on it. Recently I let my fiance borrow it for about a month and of course when I got it back something wasn't quite right. No matter what gear/RPM I'm at I get pretty bad vibrations between ~25 to 50 mph. It is the worst when accelerating through this range, moderate when cruising there and almost nonexistent when my foot is not on the gas. I went and had the alignment checked out (everything was good) and all the tires rebalanced and this seemed to reduce the vibrations but they still exist. She claims they started halfway through her 800 mile trip on some rough roads in Louisiana and continued to drive it for the month after they started. Is it possible a wheel was just out of balance and the extended driving broke something else? Am I even on the right path of diagnosing and fixing this issue? Thanks for the help.

 

Mine did the same a few years back. It was a bad u-joint. Only reason I found out was after a few weeks of this, the u-joint finally started to squeak. Replaced all the joints even though only one was bad.

 

Louisiana? Maybe she got mud in her tires?
(If you haven't seen the movie My Cousin Vinny, never mind)

 

They seemed fine when I crawled up under there. The whole driveshaft could move slightly up (By design I think) and the u-joints seemed good. Unfortunately that is not something I have the skill to replace myself. Do you think there any harm in continuing to drive and waiting for the next symptoms? How noticeable was your squeak?

Definitely mud in the tires haha

 

On a second look, the front u-joint does move a little which my Haynes books says "is a sign of considerable wear" But i feel like I read somewhere in these forums that it was ok to have about 1/4" of play. Can't find it now. Any opinions?

 

The proper way and " ONLY " way to check for bad universal joints is by removing the driveshaft and manipulating each universal joint by hand feeling for tight spots as you go . There are 4 small cups filled with needle bearings on each universal joint . There is no possible way to tell they are seized when the driveshaft is connected to the truck . You may have some play from lack of lubrication . Got any grease zerks ? try giving them some grease

 

Unfortunately I have the crappy ones I can't grease. Guess next step is to find a reliable mechanic in Austin that will fix it.