have had the rear d shaft balanced twice, and finally rebuilt. Not sure if I scraped it on a rock, but it was really out of balance, and you could see it shaking while up on a rack. While trying to find the issue found out that my teraflex rear upper trackbar on one side had a bad joint. Those were nice and greased properly, but the joint just crapped out on me. Had those replaced with poly track bars. My clunk is finally gone along with some rattles I could never track down. Headed out to the hunting lease last weekend and when I get to 75 the harmonic vibe is still there, just not as bad. Taking it in tomorrow to try and balance the tires and wheels, which havent been done since 2010. Hopefully that fixes it, but we will see. I am just really frustrated and not too optimistic at this point. I've spent $240 on the dshaft and 300 plus labor on the track bars so far and get shit daily from the wife on money put into this jeep, so going on a ride is not in my best interest to keep her happy. At least I didnt have to pay for the tailgate the car wash place screwed up. I got it back today and Abra did a great job fixing it, and even fixed some other small dents from my hilift. sorry for the rant {btt}