odd vibration has me stumped

[jman050]

Ok maybe someone has some information that can help me narrow down this problem or maybe im not thinking of all the possibilities here:

1. I had a flat rear tire that I had repaired a while back. The tire was rebalanced and has since held air properly.

2. I started to notice a highway vibration or shudder about 2 months ago between 60-80 mph that would disappear outside of that mph range.

3. The vibration has no correlation with gear, throttle, or braking (if im doing 60-80 in even in neutral i can feel it)

4. I replaced my transmission a month or so ago with a 4.44 (which i love btw) and have done all preliminary maintenance (tranny filter, new diff fluid, lsd additive, etc)

5. I replaced my ball joints a week ago

6. After the transmission replacement I still have this mph related vibration that I cannot pinpoint.

Currently Im considering that I should have all wheels rotated and balanced and then the only thing I can think of is when I had my flat tire I bent the rim.

How likely is that? I have sti BBS wheels which are forged to my knowledge