Thanks fellas. I had the wife drive it Friday and I sat in the third row seat to see how it sounds back there. It was actually quieter than I expected. There is simply a rumbling noise now. She even said it is quieter than usual (due to the CV shaft). I will live with it for now. My next step would be to change one side wheel bearings just to say I did it. I also plan on borrowing a dial indicator and checking runout on the companion flange on the pinion. That will be it probably until spring.

 

Have you messed with your Ex any more now that it is spring? I have this same issue with my truck. I haven't tried as many things as you have to fix it yet, but it seems like the same damn problem. Mine is an '03 as well.

 

I quit on it. I have spent a small fortune trying to resolve it and nothing at all has. The last option I have is to change the transfer case output bearing, which means splitting the case. I now have it for sale as I bought an 01 X Limited 7.3 4x4. The new one has absolutely ZERO driveline vibes. It has a factory driveshaft with the big rubber damper on the pinion side. The bad thing is with the springs, blocks, and bigger tires, the V10 looks ten times better than the diesel. My new one is crying for a suspension change. The V10 is also significantly quicker than a stock 7.3. I will fix that with a programmer, but the V10 and 4.30's make for an impressive combo. In your case, I would start with the basics, such as check rear pinion for play and ujoint condition. Good luck with it as it gets frustrating.

 

Thanks for the reply dave. I hope mine doesn't turn out like yours. I can't afford 1/4 of what you have done to try and resolve the vibration. Hopefully mine is something simple. Sorry to hear for your misfortune, but glad you got another X. Have a good one.