New CSB, now bad vibrations

[Super Sedan]

I put in a new CSB after the last one began the dreaded squeaking noise, slapped the new one in, and now I have a bad vibration under hard acceleration, as well as at anything over 50 mph. The driveshaft did not cause a vibration before I pulled it out (which makes me rule out an out-of-balance driveshaft). It gets worse when I let off the gas. I made sure to properly preload the CSB when I put the new one in, the guibo/engine mounts are only 6 months old, all of the bolts are tight, etc. I also made sure the two halves of the driveshaft were lined up with eachother as they were when I pulled it out.

I read that it may be the "splined sleeve collar nut" which keeps the two pieces of the driveshaft connected - if you over tighten this nut, it can bind and not allow the driveshaft to move in and out. This is something I plan on checking out but if any of you guys have some advice, I will try that as well.

Let me know
-Joel

[jlevie]

The drive shaft length doesn't change while the car is being driven. That adjustment is there to allow the drive shaft to be removed/installed and to accommodate manufacturing variations.

A vibration that occurs when the drive shaft is subjected to high torque loads is almost always going to be caused by binding u-joints. The only fix for that is replacement of the drive shaft with a new or rebuilt unit.

[Super Sedan]

Thanks for the feedback, Jim. I am still unsure as to how this would suddenly happen as it was working fine (no similar vibrations) before I pulled it out?

[jlevie]

That is not an uncommon occurrence when dealing with a failing drive shaft.

[backwoodsE30]

i just learned this drive shaft/u-joint lesson myself it SUCKS why is it not serviceable!