It started with a whine at acceleration. Then the whine went away, but a strange vibrating rumble came in - usually when accelerating in second gear, so low speed. I was sure my AT was going to die. And I also started getting this high speed vibration at around 83mph which would go away around 86mph, and would come back around 93mph.
Then it hit me: it must be the center support bearing.
Replaced the center support bearing and the problems at low speed are gone! Whew, it was NOT my A/T.
Now, lets hope that high speed vibration is gone too. If not, I am thinking it must be differential bushings.
Both vibrations were mostly felt in my seat, not in the front, but from the middle/rear of the car...
So in case you have the same problem you know what to do!

 

What is the center support bearing???

 

I believe peterls is referring to #15 on this diagram.

 

Yup, that's it.
Glad to report that high-speed vibration is gone too. Feels good to nail such a hard to diagnose problem on the first shot!

 

Just found this old post, want to add something for lurkers: if you want to replace center support bearing, do NOT use an aftermarket one. I decided to risk it and bought a new, cheap one from e-bay, for $55 and it is already making noises, only two years later. It is OK, but I can hear it whine from time to time, so the quality is in the crapper. Stay away from non-oem parts. I will replace this with OEM first chance I get.

 

Thanks for the update

 

Thanks Peter.Posts like yours always make me feel better when buying pricey OEM parts.

 

I bought an entire driveshaft from an JY with 95k miles for $55. So this might be the easier route since you won't have to pay a machine shop to press it on/off. I also got better condition rubber driveshaft bushings along with the swap that fixed my cracked and dried out AZ ones.

 

 

I have a 2010 gs 350 with 150k one morning when I was going to work my rear of the vehicle start vibrating over 50 when I took it to the shop there was a P0204 injector open closed circuit short I changed the ecm and injector driver also the 4 injector and coil pack the shop seem to canter find the issue can some one please help me out

 

I second valex's question, and add my own: i have a 1997 ls400. The center support bearing, what is the latest year that uses the same bearing? For the option of finding a newer bearing from my local pick a part yard.

 

wrong forum: i understand this forum is for the beloved LS400

 

I ordered one that says OE replacement from rock auto. Is that good?

 

Where can one acquire just the ujoint

 

'OE replacement' is not OE. that's just jargon for 'aftermarket'.

I found that a lot of the vibrations are mitigated/removed just by replacing the transmission mount alone, not the center bearing.
the mount is very easy to replace and relatively cheap compared to the bearing.
the mount usually tears at 100k and upon close inspection looks fine, but mine was totally separated when uninstalled!