Drive Line Vibration after replacing Ujoints

[DCasal]

I have an 04. 5 3500 SRW with 6 speed, replaced factory joints on rear shaft at 44k with precision 351. Now at 123k had to replace the joints again. Used the same same joints precision 351's. The joints installed easily work nice and free but drive down the road I now have a drive line vibration at about 28mph goes away SOME and comes back in heavy around 60. Popped all the joints out and replaced them again saw nothing wrong with the ones I took out but why chance it. I still have the vibration. It is coming from the rear as you can feel it in the seat and floor. This vibration is new since changing the joints and I can not find anything wrong. It is not a shudder it will vibrate your teeth out. Also truck is stock everything, and load or no load, makes no difference on the vibration. Any and all suggestions welcome thanks

 

[JApol]

Two quick questions, you talk about your rear drive shaft so you have a 4x4 right?

Also you have a carrier bearing being a long bed right?



If you have a carrier bearing check it for play.

If you have a 4x4, take out the rear shaft and rotate it 180* and reinsall. Most of the front/rear drive shafts are tuned together.

If that doesn't work remove the front shaft and check again.

I replaced my u-joints about 1. 5 years ago and never totally got rid of the vibration. I had the shaft balanced and it made a world of differance.



Good luck with your fix and welcome to the forums

 

[DCasal]

Thanks for your response, it is a 4x4 long bed and I have checked the carrier bearing. I also removed the front drive shaft to eliminate the front end shaft. I can get the vibration with the rear of the vehicle on stands and driving at speed. If you meant split the rear shaft and rotate it 180 that was my next move. What makes it strange it started as soon as I changed the joints.

 

[JLandry]

DCasal,



Are the end yokes of the rear propeller shaft "in phase. " Check out this picture and notice how the end yokes line up:



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I wonder if when you changed the u-joints you pulled the rear propeller shaft apart, and then when you slid the splined shafts back together the yokes at each end weren't lined up.



Having said that, since I've never had to replace the u-joints on my Dodge truck yet, I don't even know if the rear propeller shaft can be pulled apart and reassembled out of phase. My apologies if this isn't possible.



Best regards,



John L.

 

[DCasal]

Problem is fixed and big lesson learned. The night I was putting in the joints the power went out and was working with a lantern as my generator was on a job site, I always mark the shaft, well I guess I missed the mark. Today I pulled the shaft again and rotated the rear half 180 no more vibration. Lesson learned mark it good and pay attention thanks for the responses.