Well, I'm going to bite the bullet and try to get my transmission sorted out.
1979 280SE 116.024, transmission 722.112, God only knows how many miles, engine good, drivetrain good. Fluids new and correct level.
Transmission allows engine to high rev (flare, slip, etc.) between 2-3 and 3-4 with normal throttle. A bit more throttle - not good; easing off allows shift.
What I'm gonna do...
Not going to take it out and apart. Oil pan down and what can be reached only . I am skilled as a mechanic, but I never got into the automatic transmissions. Not afraid of them, just don't know 'em.
I got the ATSG 722.1 manual, but it is mostly disassembly. I have the tools, pressure gages, I just got to crawl underneath and figure out adapters.
What I need is a diagram of the test points and the threads for the measuring adapter(s).
Then I want to fix it.
I would suspect the bands or clutch plates are all worn out. Requires complete disassembly.
I rebuilt a th350 once, could not beleive how much red atf poured out forever.
For $1700 just have sun valley rebuild it or if you enjoy the work, find a complete rebuild kit and have some fun and learn something new.