Finally took my 96 PSD into a shop today for diagnostic scan. Code P0741 causing a P1728 slip fault. And that 741 code won't clear. The shop is guessing the PCM is at fault now(?)
Because its a Montana truck that's been driven in WA, ID, MT, UT & WY extensively I'd think corrosion at PCM connector could be a cause perhaps(?)

Wasn't getting any response over at the transmission forum here on FTE:
https://www.ford-trucks.com/forums/1617085-96-97-4x4-e4ods.html

P0741 code
https://www.troublecodes.net/pcodes/p0741/

 

It could be the PCM, the Torque Converter Clutch solenoid, or most likely, a damaged wire between those two.

 

The shop found an add-on module with harness to the PCM. They bypassed this & the P0741 code cleared.
They had tried another solenoid pack to make sure it wasn't a harness problem. Now the TCC is working.
But, L/R clutch pack still is slipping at times so I'm having a complete O/H & upgrades to this E4OD.

When I get my truck back I'll get some pics of this mystery module & harness.

 

Apparently some PO had added this BD-Power pressureloc #1060380 to the trans harness. I'm the 4th owner of this 1996 F250 so I don't have the complete history of what was done in yrs past. There's an add-on harness from this unit to trans harness for control of lockup I guess.
BUT, it wasn't working at all due to connection(s) on board heating up & dripping solder, thus causing shorts. Knew something was wrong when I heard rattles shaking the control box...
I think this failed unit is what burned up the TC friction disk as it acted like a compression brake in 2 & 1 while coming to a stop. I could feel a shudder that's not there now.
Stripped everything BD-powerloc out of my truck after I got home.
E4OD trans had some burnt frictions & steels plus L/R sprag had grenaded. Upgrades were done like forward planetary, etc.Trans case, center support & alum pistons were all fine according to shop mgr.
IF I had had the space to do it, would've overhauled it myself. Shifts great, clean & quick but not too hard. Can definitely feel 4th gr lockup now.