Vibration Under Load

[nblanton]

I think you have a bent drive shaft. I had the same trouble for almost 2 years before I finally had the drive shaft looked at. I went through three pinion yokes and two t-case output bushings during the troubleshooting. The vibes would smooth out for a while when I would put a new bushing or pinion yoke in until the vibes wore out one or the other. The drive shaft looked fine until the guys at the drive shaft shop put on their balancer where you could see the wobble. Its pretty hard to discern a bent shaft unless you got access to a lathe or a lot of V-blocks. Getting my shaft re-tubed only ran about $100. It was completely worth it and solved all my problems.

 

[breecher_7]

I think you have a bent drive shaft. I had the same trouble for almost 2 years before I finally had the drive shaft looked at. I went through three pinion yokes and two t-case output bushings during the troubleshooting. The vibes would smooth out for a while when I would put a new bushing or pinion yoke in until the vibes wore out one or the other. The drive shaft looked fine until the guys at the drive shaft shop put on their balancer where you could see the wobble. Its pretty hard to discern a bent shaft unless you got access to a lathe or a lot of V-blocks. Getting my shaft re-tubed only ran about $100. It was completely worth it and solved all my problems.

Will definitly do this, I have a lathe and plenty of V-blocks at work, so I can take a quick look at it myself, all this crap will have to wait till spring though, just gonna have to drive it the way it is till winter is over.

Ill have to take a closer look at the pinion bearing and output shaft bearing next time I get it up on the lift.

If anyone else has any further ideas, im still listening!

 

[tsill]

Pull the front shaft. Still have vibes? Yes. Reinstall. Its in the rear end or tires.
No. Front shaft rebuild/rebalance or Front pinion bearing.
Pull the rear shaft. Still have vibes? Yes? Something in Trans/Tranfer Case/Rear End.
No? assuming there were no vibes after removal of front shaft, and running in 4hi on front shaft then rebuild/rebalance the rear shaft.

The next question would be after pulling the rear shaft and still having vibes, which sounds like what your case will be, how do you determine where the vibes are coming from.
Would the trans output bearing still make vibes at 60-65 mph if it had no driveshaft attached.
How about the pinion bearing in the rear? Would it still vibe if it was bad but had no load on it?

Pull your shafts like everyone here suggested and start from there.