well a few weeks ago i replaced my u-joints. i marked where the yokes attached so i could replace it in the same position. then i marked the CV so i could get it back together. Once i got the CV done i forgot to mark the single joint.Now Im getting some vibration when itake my foot off the gas at higher speeds, like 65-75. its not as severe as before i replaced the joints. its like a purr now. when i accelearate the vibration stops. everything looks ok underneath.

Would a drive shaft shop rebalance it if i took it out. The only driveshaft shop around said they dont doLR.I doubt they could tell the differenceit if was on the counter.might have to drive it over in my girlfriends explorer.

 

I always wondered how much of a difference it made having everything lined up correctly, but obviously I never wanted to try. If your sure it's just the one joint, I would take the shaft off, flip the yoke 180 degrees and reattach.You had a 50/50 shot,you must have guessed wrong.That may not even be the problem, but it's not too hard to do.

 

If all the joints grease fitting are pointing in the same direction, it can throw the balance. How about the centering ball kit, did you replace it also?

 

Yeah i replaced the centering ball kit too. I used precision u-joints and centering ball in the cv. and yes the fittings are lined up. i didnt think about it throwing the balance. i was just thinking about accesibility.

but i used neapco on the lone u-joint, the one with the nipple on one of the caps. couldnt find three of the same joints, searched everywhere. i figured it would be better to use the 2precisions in the CV.

i would take it apart and mess with it but i had to rent a 150 ball joint tool from advance and i dont wanna go through the hassle of getting it back. i was hoping it could be cheaply rebalanced.

 

This is exactly why I paid to have mine done. They were balanced..

 

I'd get that baby looked at. Pretty cheap in comparison to having it shred your tranny. On a side note, you sure the vibration isn't the rear drive shaft flex coupler? That'll cause vibration when you let off the gas.
[align=left] [/align]

 

My grease zerks are all lined up of the shaft and I have no problems. I'd wouldn't be surprised if the vibration was something else. I suppose you could pop the shaft off and drive around to see. (if you have a cdl)

 

Thanks for all the replies!

I wasnt thinking about the flex coupler, ill check and see if its chewed up tonight.

 

I checked the flex couplerlast night. It looks good for the most part. There are some surface cracks around the three bolts attached to the driveshaft. Is that normal? The cracks didnt seem too threatening.

The front driveshaft still looks good, theres no play in the shaft.

Would such small cracks in the rotoflex cause a vibration?

 

No, the small surface cracks in you flex joint should not cause the vibration.