Drive Shaft Center Support Bearing Diagnostic Help!!

(2010 Tacoma Base 2.7 4X4)
So I was recently having problems with my driveshaft. When accelerating, it would make the truck shake and rumble. I had a mechanic look at it and he said that I needed to replace the drive shaft($1600). I did not like the price at all and looked into it myself. I found out that it wasn't the whole drive shaft, but that the drive shaft center support bearing was bad and needed replacement. After replacing the center support bearing as well as two u-joints, the truck still has a lot of vibration and rumbling...only when I accelerate. When going slow every things fine.
I don't want to have to spend the $$$ to get this fixed if I can do it. Any thoughts of what else it could be that I might have missed?
Thanks a lot!

 

are you lifted? might need a carrier bearing spacer

 

fatfurious2 Its not lifted.Id say its your average hight on a truck.

 

Motor mounts? I am not sure. Hopefully others can chime in