Meh. This sound has started grating on me again lately. I don't think anything has changed, I just think I can't quit focusing on it. I'm still convinced that it's gear noise, and there's some kind of resonance that makes it more noticeable at certain rev ranges. 1700-2500RPM in 3rd and 4th are the worst. Below those revs it builds continuously from an unobjectionable whir to the nasty whine that peaks in the low 2k's. I went for a joyride this morning and discovered that there is NO problem if:
-I keep my foot
all the way in it
-I keep the revs well above 3k
Sounds great under those circumstances.
Sadly that's not really a solution. I crawled under it earlier in the day to check mounts, heat shields, shift linkage, etc. for any obvious problems. One of the bolts on the trans mount bracket was a touch loose but snugging it up didn't help. I also didn't see anything weird like poly mounts installed by the PO or a short shift kit with hard bushings. And everything around the trans appears to be in its proper place.
So I'm a little torn. The trans fluid change did wonders after about 500mi of letting the new fluid work...great shift action, no more lockouts. But the sound is soooo annoying.