JBLADEN

Hi, first post but been a long time lurker here. Been searching driveshaft vibration posts, couldn't find anything specifically useful regarding replacing the "staked-in" universal joint. Book says to replace entire driveshaft with a new unit, which I'd gladly due but they are NLA. While changing the center bearing, I discovered the u joint has tight spots in its movement. Verified driveshaft sections were angled properly by the book.
As per the video, the vibration is clearly being transmitted thru the center bearing, which is adjacent to the u joint. Additionally, the bearing housing can be seen wallowing around slightly at hot idle speeds in 1st gear.
Apparently this u joint has some unusual dimensions making stake-in and c clip joints unattainable. Complicating matters further, the u joint yokes lack flat spots for c clip type joints.
Talked to a dozen driveshaft shops all over the country regarding u joint replacement, only one said they can help is Action Machine. They said I would have to ship my driveshaft to Indiana, then they would ship it to California. Personally, I don't have confidence with them, partially they won't let me ship or call their California facility directly..
Another alternative is changing it over to a on piece shaft from Driftmotion. https://www.driftmotion.com/searchre...h=3327&Submit= Been considering this but was informed by Driftmotion, the one piece shafts do transmit drivetrain noise inside the car as it eliminates the rubber driveshaft donuts on each end.
Anyone have experience with Action Machine or Driftmotion? Any comments of recommendations would be greatly appreciated. I should mention the car is completely stock and plan to keep it that way. Thanks again.

95SnowCoup

I have the same problem from my driveshaft except i get it when ever i let off the gas at highway speeds it makes a very loud vibration noise from the center of the car (not louder than the radio tho ). I've also had problems trying to find ways to replace the center bearing but Ive fallen into a few different rabbit holes and there are other cars with the same rubber driveshaft coupling and center bearing set up for their driveshafts. <- this is a video on a BMW model car (i hate them but they have the same drive shaft setup) and this video shows it being completely possible to replace on your own no driveshaft replace needed, then again it doesn't necessarily mean the driveshaft center bearing on the SC is replaceable like the BMW models is.

<- here is another video by CartuneNZ he is a literal wizard for any information about the 1UZ and 1UZ powered cars. this video is a in-depth description of the LS400 driveshaft im not sure if the driveshafts are different between the LS and SC but they share the same tranny so it shouldn't be too different. Id also shoot CartuneNZ a comment or DM asking a couple questions about it he would definitely know.

Sorry this isn't an exact fix but i hope i gave you enough different avenues to go to help you find more answers than i found during my search good luck fixing it m8

P.S don't let anyone tell you it isn't fixable

JBLADEN

Thanks for the reply and the links 95SnowCoup. I did replace the center bearing, the old bearing was tight and smooth. Replaced it due to the weight of the driveshaft over time compressed it's rubber mounting system making it off-center affecting driveshaft alignment. Changing the center bearing wasn't too difficult, used a clamshell and a 2 jaw puller to remove and made a driver to install it. Other things I did chasing vibration problems is balance tires and replace the motor mounts new OEM parts. Replacing mounts was a tough job, fortunately, I had the transmission and catalytic convertors out to replace the leaking rear main seal. Prior to changing the mounts, it would vibrate worse under load, less when placed in neutral at speed. I'm reasonably confident it's a u joint issue, as when I had the driveshaft apart at the spline to replace the center bearing, it was easy to note the u joint tight spots throughout it's movement. Still searching for a shop that can replace staked-in u joints.

RXRodger

iTrader: (2)

I have had Driveline Service of North Atlanta rework a couple. Less than $400 for the last one, should be a topic on here somewhere I either started or added to. You just send them yours and they replace the u joints and balance. There are a few out there, most shops won't touch one with the centering bushing type like SC's and BMW's have. That's the issue with trying to replace just the u joint, as you have found out not available anywhere even if you wanted to try it yourself. I couldn't find them anyway.

Driveline Service of North Atlanta

It does sound like that is the source of your vibration since you have noted the u joints are notchy. Common problem. I need to send my spare out soon so this will be my third for the SC's to go to them, been a couple of years since I have had it done hopefully they made it through covid ok and still doing the service.

One time on a BMW with similar driveshaft and issue I went as far as drilling holes in the back of the caps and greased with a needle tip, sealed up the holes with one of the industrial epoxies. There is just too much centrifugal force, the epoxy didn't hold, although it did fix the "tunnel womp" temporarily.

JBLADEN

Thanks RXRoger for the reply. I just called Drive Line of North Atlanta and spoke to Andrew who stated in the past they would replace the staked in joint with various Mercedes parts. Andrew stated that fix does not last long. Bottom line is they can't offer a fix. Andrew did take the Lexus complete shaft part number from me, 37100-24380 and is going to research sources to fabricate a new one from scratch. Awaiting a call back from Andrew, I'll let you know.

RXRodger

iTrader: (2)

Thats interesting since they have done two for me. Maybe change of the office people since then. The work they did on both of mine has held up. One is on a race car with lots of track hours on it since the repair.

JBLADEN

From your list of SCs, looks like you have 300s. Think 400s use a different shaft, I was referred to Driveshaft Pro in Garden Grove California who stated they can't help since it's a 400. Note they have this offering for the 300. https://www.driveshaftpro.com/garden...&trans=Manual&

RXRodger

iTrader: (2)

Ah, didn’t catch that. And I wouldn’t have thought that would have mattered as far as them doing the repairs. Interesting.