Just replaced the center u joint on my 65 544. I was very careful to mark the edges of the flanges so it would go back together the same way BUT I didn't make sure the flange went back on the drives haft the same way. It was a 50 50 chance, so naturally I put it on 180 degrees out. Never occurred to me to also mark the original position before replacing the u joint.
When I drove the car there was a pronounced high frequency vibration because of the out of balance drive shaft.
Took it apart again, reversed the flange and all is well. Had me wondering for awaile what I did wrong but it finally came to me.
Hope this keeps someone else from making the same mistake. Tom
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