Nasty Tailshaft Vibration - Please Help!

CNS45 · 12-22-2005, 11:35 PM

Thanks for your help. Here is some further info: I knew I had a wheel bearing that needed replacing on the front left, but that has been done & all others are ok. Its not a wheel balance or alignment issue, as that was done also. Yes, I have felt the vibration & the web site I quoted seems to explain it the best when it says: "...This can sometimes be felt as an incurable vibration in the car which gets worse as the speed builds up."
The Vibration is defintely coming from the behind me & feels like its located at the center of the vehicle where the drive shaft runs.

Here are some of the other replies I've gotten on another Supra Forum. Might they be right?:

are you missing any of the counter weights welded onto the shaft that balances it...the part about the universal joints lining up is called in phase and if it is out of phase that can cause the shaft to turn at different speeds depending on the angle in the shaft....but yours is a balancing problem,a transmission specialist should be able to balance the shaft for you.

&

It's very rare for a tailshaft to go out of balance for no reason at all. Tailshaft vibrations are far more likely to occur because of a dodgy centre bearing and/or worn uni's. Either way, take it to a driveline specialist and they'll be able to tell you exactly what the deal is.

Any input is greatly appreciated. I've already thrown thousands of dollars at this car fixing issues & dont want to waste my money trying to find & fix a problem using too much "guess work". If I can narrow it down to a couple of things that will need to be checked, i'm sure that will be cheaper in the long run. Thanks again.

12-22-2005, 11:35 PM	#3
CNS45 Stock Join Date: Dec 2005 Posts: 2	Thanks for your help. Here is some further info: I knew I had a wheel bearing that needed replacing on the front left, but that has been done & all others are ok. Its not a wheel balance or alignment issue, as that was done also. Yes, I have felt the vibration & the web site I quoted seems to explain it the best when it says: "...This can sometimes be felt as an incurable vibration in the car which gets worse as the speed builds up." The Vibration is defintely coming from the behind me & feels like its located at the center of the vehicle where the drive shaft runs. Here are some of the other replies I've gotten on another Supra Forum. Might they be right?: are you missing any of the counter weights welded onto the shaft that balances it...the part about the universal joints lining up is called in phase and if it is out of phase that can cause the shaft to turn at different speeds depending on the angle in the shaft....but yours is a balancing problem,a transmission specialist should be able to balance the shaft for you. & It's very rare for a tailshaft to go out of balance for no reason at all. Tailshaft vibrations are far more likely to occur because of a dodgy centre bearing and/or worn uni's. Either way, take it to a driveline specialist and they'll be able to tell you exactly what the deal is. Any input is greatly appreciated. I've already thrown thousands of dollars at this car fixing issues & dont want to waste my money trying to find & fix a problem using too much "guess work". If I can narrow it down to a couple of things that will need to be checked, i'm sure that will be cheaper in the long run. Thanks again.