My guess at this point is that you didn't back off the band adjustment enough and burnt up the intermediate band and/or drum. There are seals inside the drum for clutch actuation (I'll take a look at my schematics today for some particulars) and if things got hot enough, may have cooked them, causing a loss in hydraulic pressure to actuate the clutch pack....
Normally, I give the intermediate band adjuster (with locknut loose) a moderate pull with a short (4") handled end wrench, then back it off 1.5 turns and then, while holding the adjuster, tighten the locknut.
How does this compare to what you did....?
BTW, I also had a sluggish 2-3 shift when I bought my D-coder back in '93 but the installation of a shift kit cleaned that right up...the trans now has 199.4K on it and shifts like new....shift kits are worth every nickel...I did adjust the bands when I installed the kit but they were right within spec...C4's are a durable tranny if maintained...
You may have to punt on this one....scrounge up 400-600.00 and get a rebuilt tranny and converter....
Try posting a new inquiry once you have more info and reference the previous three threads in your post....some of the gang who know this stuff may have been away as I have been...
Good luck!!
Pat
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