47re, no OD, no lockup

[2001cumminsman]

I need some help diagnosing my 47re, long story short I picked up a supposed to be built trans from a buddy (he didn't have paperwork) but I trusted him so thought I'd be fine. Got it in and the shifts aren't as hard as my last built transmission but shifts 1-3 fine, but it will not go into overdrive. The torque converter won't lockup unless I do it manually with my lockup switch, and in 3rd at wot it almost acts like it drops into neutral then as I let off the throttle it slams back into 3rd... Sorry for the vague discription, but where do I even start diagnosing this thing? Check line pressure? Replace my relay in place of my jumper for the lockup switch? Solenoid in the transmission perhaps? Throttle valve cable possibly? I couldn't find an exact write up of how to adjust it so I haven't messed with it. Codes were as follows p0743, 0500, 1765.

 

[8UPRACIN]

Same year trans as our old one? I believe the electronics internally are different and may not be communicating with your ECM/PCM

 

[Big Blue24]

I'd put a pressure gauge on the OD port and see if any pressure is making it back to try and apply overdrive. On core/burned up transmissions, it's common to see burned up overdrive clutches and usually the culprit is a torn or damaged overdrive piston seal. Putting a gauge there will let you see if it's building the 10 to 20 psi indicating a torn seal, as opposed to a healthy OD piston which will read 90+ psi depending on how much line pressure the VB is building, could see 200ish on a hotrod tranny.

 

[2001cumminsman]

I swapped out the tcc/od solenoids from my old transmission to the new one and that fixed the problem, I had the throttle cable out of adjustment also. Everything is shifting and working fine, but now during a 4wd launch leaving at 18ish psi I can smell clutches, line pressure is 155ish at wot through 3rd and at one point I thought the gauge showed 180 in od and locked up. Would replacing the governor solenoid with the gm solenoid be a good idea? I feel like I need to increase line pressure so those clutches don't slip again, if all my shifting is fine and I increase line pressure 30psi or so do I still need to turn the tv valve screw 1/2 a turn or so?