Thanks for all the help. Just a little update....I checked my driveshaft and found that there was way too much play when I shook it back and forth. I found that the u-joint was in sad shape with the bearings starting to blow out. I replaced that and the vibration is almost gone. I have a feeling like solidblk85 suggests it may be the support bearing, in fact I was just talking to one of the buds about borrowing his garage so I could change it. I will be replacing it in the next couple weeks and I suspect all vibration will be gone. I keep you posted.