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regular87

I bought an Oldsmobile F-85 about 2 years ago that was in moderate shape. Only 50,000 miles on the clock. However, since the day I got it, it has had a strange driveline wobble. It is most extreme at around 30mph then seems to get better.

In an attempt to fix it, i recently had the driveshaft totally rebuilt and balanced. I was told the U-joints were pretty well shot and the hanger bearing was totally gone. It cost me around $300.

After re-installing it, the problems mostly returned very quickly. It is much better than it was, but it still makes an audible clicking noise at low speeds and has a very noticeable vibration. To make matters worse, I jacked the car up and noticed that a fair amount of play has returned to the U-joints between the slip yoke and rear shaft.

Anyone have any ideas?

tooltime47

I had one of these back in the sixties. I had to replace the u-joints several times. I think it was a common problem. However, the problem should not have re-occured that quickly. You must have something severly out of line.

SuperDave

I am not familiar with this particular drive shaft, but...I assume it's a two piece shaft? Some slip joints can be assembled wrong. And Murphey's law being what it is........ often do get assembled wrong. All the U joints must have the same axis . Just having the slip joint one spline off will set up some strange vibrations. Make sure all three are lined up. U joints don't move smoothly through the rotation. They speed up and slow down at different times during the rotation. Depending on the angle that it is trying to correct. When all three act in unison, no problem. When they get out of phase they can set up some really strange harmonics. Hope this helps rather than confuses..

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