Went to chase down a vacuum leak and, in the process, noticed a strange noise coming from the transmission. It was making a whining / loping metal on metal sound. I found the transmission had separated from the bell housing by about 1/4". I pressed up on the bottom of the pan and the noise went away. I guess it was all that stress on the shaft and bearings causing the noise.
Anyway, I suspect it was caused by one of the bellhousing to tansmission bolts that came loose last year I and I had to bore a hole in the bell housing to fish it out before it destroyed the converter. Either they were all loose and bound to come out in the first place or the missing 6th bolt allowed the others to come loose too.
I removed the transmission last night and fixed the issue with locktite. Oh how I had forgotten how miserable it is to remove that transmission without a transmission jack and an extra hand.
Can't wait to do it all again for the 4R70W this spring. I think I will snag a proper jack though!
BTW- Changed the rear main seal while I was in there since it has to be done with the flexplate removed.