I’m pretty sure your problem is with the overrunning clutch. Putting it in “low first” applies the rear band, which does the job of the overrunning clutch, that’s why “low first” works when normal “drive first” does not. In third gear, the front and rear clutches are engaged, and the overrunning clutch is not needed. In reverse, the rear band is also applied, which explains why reverse still functions. Unfortunately the transmission would have to be completely disassembled to repair that.
That's what this chart is showing me...
I wasn't aware my transmission had an overrunning clutch! I rebuilt it and never once heard or read anything about an overrunning clutch. That's literally the only part of my tranny I didn't mess with when I rebuilt it!
Update: I was refering to the output shaft support that I didnt mess with... I didnt realize the sprag and overrunning clutch were the same thing. I took the rollers and springs out and cleaned them, I inspected everything and the rollers and springs looked new! There was a little wear in a couple of spots from the roller bearings but I smoothed that out... I also oiled it before assembly...
How though?! It was working perfectly when I installed it!
I'd like to do a pressure test to rule out any other possibilities before I pull it.
Could a damaged servo seal cause the same problem? Will a pressure test pinpoint the problem???
Maybe a rubber mallet could help knock something back into place or unstick something?
