Transmission Squealing

[crawdad]

Took the 85 out on another test run today to check out the power steering. When I got home and had it idling, I heard, what I thought was a fan belt squealing. I opened the hood and it was quiet under the hood. I stuck my head under the truck and it sounded like it was coming from the transmission, more on the passenger side than the drivers side. The tranny pulls real good and seems to work well in all gears (although the shift points are REAL close together). Sound does not go away as I shift it through the gears, nor does it go away when I rev it up, although it does seem to get quieter. When I shut the engine off, the noise seemed to just bleed off, almost like a vacuum leak loosing air or something. I really don't think anything is wrong with the tranny itself, but is there anything on the tranny that could cause a squealing like this? Would appreciate your ideas/suggestions. Thanks.