apparently NO TC lock-up

[mile-hi-bri]

Thought I would throw out an interesting 'problem' I recently installed a 'used, low mileage' trans. Adjusted TPS, and did the band adjust, (both, per the GREAT How-to's, thanks!). Also back-flushed the rad cooler while OUT of car.(no new cooler yet). New trans filter inside AND out. Everything is wonderful. Crisp shifts, no flare,(TPS adjustment BTW)BUT!
There is no RPM change EVER in 4th gear, as if it is NOT doing a TC lock-up. No matter throttle position, uphill or downhill. The RPM's don't vary like they should? Help.! I'm stumped.
I went back thru old posts, found miles of discussion about lock-up in 2nd/3rd/4th etc.
Didn't Aredubjey have the same problem a long time ago? Didn't see a resolution to his problem.
Obviously, any help is much appreciated. It is sooo wonderful to not be alone in the wacky world of SVX diagnostics!!
Thanks again, Brian