I to have seen vibrations blow up a transfer case on this forum more then once. If its the front i would take it off till you can sort it out. Best of luck man.

 

So assuming its the new driveshaft, what are my options?

I figured:
1. Adjust the pinion angle to more closely match the shaft angle
2. Get shorter coils which will bring the txfr case and pinion closer to the same plane (this also helps with the CA angle too)
3. Save up and get a HP D44 or D60
4. Or just say fuck it and sell the jeep

There has got to be 100s if not 1000s of jeeps that have 4" lift and aftermarket shafts that are working just fine. Is each case having its own special circumstances that makes it work or not?

 

I adjusted my upper arms last night to point my pinion up some. It reduced the vibration quite a bit. I'd try that first, took 30 mins.

 

Yeah I'm going to try that route first. Then try new springs if that doesn't work (surely dropping 1.5" off my lift will help).

Tell me this what did the vibration feel like, or rather where was the feedback coming from (e.g. steering wheel, gas/clutch pedal, or the shifter) that made u think it was the DS vibrating?

 

Mine felt more like a rumble in the floor board that got worse the faster I went. Started around 70 mph. You could feel and hear it. Much better now but I could maybe still go up a little more.

 

Good to know. Maybe I am being overly pessimistic about my situation. Definitely not a rumble. And not really any sounds that I could hear to go along with what I am feeling. It's almost like the floor board is vibrating. I also thought I felt the same vibration in the clutch when my foot was resting on it but then I noticed tonite sitting at a light that it felt the same. I feel the same thing in the steering wheel. So now I'm wondering if I'm just going crazy.

 

I unfortunately belong to that club.
Started with a Coast 1350 and got to the point where I was having the ujoints replaced every 3 months no joke. It had vibrations, angle was bad, blah blah blah. Even with a PR44 Unlimited I was getting vibes and finally had a local driveline shop take a look and they noticed that the angles we're still a little bad and the adapter plates were Coast first generation and were mangled maybe causing some balance issues who knows. Anyway I had them build me a new driveshaft using yokes versus plates and have never had another problem with the front. Hope you figure out the problem and take extra caution if you have vibrations that aren't wheel related make sure you have your DS looked at...assumes your setup is good and angles corrected.

 

When you refer to plates do you mean ends at each joint that would attach to the stock yokes?

When I installed mine I had to take both my stock ones off and replace with the yokes from the coast shaft.

So was yours caused by the adapter plates or the shaft itself. Not sure I followed you on that. Thanks for the input.