I'm sorry for the extreme length of this but, as you can see ive tried everything and i'm really at a loss. I don't want to bring it to a shop but I may have to...

96 f350, 2wd E4OD
Started out, my forward planetary crapped out..not sure why, but it did.

I rebuilt it myself with new torque converter, remand pump, remand solenoid body, and the tugger HD kit. Also has the deeper 4wd pan and filter.

Installed everything, drove it and no 3rd gear. Just got to about 2200 rpm and it wasn't happy. No 3rd, no 4th.

Dropped the pan, swapped out the solenoid pack for the old one, also checked for stuck shift valve... they ALL sprung back correctly.

Everything back together, no change.

Pulled the pan, ran an air test (admittedly i did not do this at all during rebuild) but it was hard to get into the direct clutch port, i got it as best I could and thought I heard a good thud but couldn't be 100%. Got good Thuds on everything else. Also checked again for stuck valves.
At this time i also checked continuity on all the wires on the tail housing harness, checked resistance on the shift indicator, pulled the VSS sensor, checked tps voltage... everything checked out. I cleaned all the plugs including the vss sensor. My tach and speedo have always worked fine, no weird things.

None of that made a difference.

I finally said screw it, I thought maybe i rolled a seal or something in one of the clutches.. pulled the trans, pulled the clutch drums, they all passed the bench air test. I did have a little trouble with the direct clutch. It had an awesome thud when I tested it on the bench but when i.put it on the center support, it seemed to be leaking on the shaft where the metal sealing rings were. I applied some atf, and it sounded much better until the atf flowed away and I was back to an air leak. I chalked that up to passing, and proceeded to put everything back together.

threw it back in the truck and no change. Up to this point, i hadnt had a good way to check line pressure.. I had a gauge but not a long enough hose... finally cobbled one up and did some testing. I have 200psi stall pressure In D which I'm seeing is okay, I did not to a reverse stall test yet but idle pressure was 100psi. All other pressures were Okay at idle... drive was the only one I did a Stall test on.
also unplugged the solenoid pack and still no shift to 3rd. Im still a little hazy on what is supposed to occur in limp mode, but i didnt feel like much changed. Even though i was on jack stands, it still felt like it did the 1-2 and then no 3rd..so if someone wants to chime in on that?
At this time i started digging more into my OBD app to see if i could find anything to help. Through all of this ive never ever had a trans code or any other P code. Also passes both self tests.
I monitored the shift solenoids... the are turning on and off at every shift just like the should. The computer is commanding 3rd gear but nothing is happening.

that's where Im sitting right now. The only other test I can think to do is to test the inputs at the solenoid to make sure they are even getting the command signal from the pcm. Please, if I'm an idiot for not seeing something, tell me lol. I miss my truck and I don't always have alot of time to work on it. I hate bringing things to the shop especially when I can't afford it... I have more time for testing than I do money for a shop.

I have a couple videos of when I was doing the idle pressure checks if those would help. Also, I have no changed the external cooler yet. I keep forgetting to order one. I've blown through it more than once and everything seems to go okay?

 

And the direct clutch is the one that needs to apply for third and fourth gears. Go figure.

You found a problem that most likely has caused your issue and ignored it. No wonder there was no change.

And reverse was the only stall test that would have helped to diagnose this problem. The direct clutch is not on in first gear.

The trans will NEVER be in third gear with the shift solenoids unplugged. In manual 1 and 2 you will have second gear, in OD you will have fourth gear, and reverse will be reverse.

With the solenoid body unplugged it will not shift at all. Period.

All of this eliminates the possibility of anything electrical causing this. It is a mechanical problem inside the transmission. That leak you found on the center support sounds more and more like the problem.

That's always fun to do, but it certainly won't fix this problem.

The cooler can trap debris. It may or may not work itself loose over the next several years. This fine debris is perfect for sticking valves and solenoids. Are you feeling lucky?

 

I was leaning towards this, but let me ask... if direct clutch was no bueno and leaking... would I still have good reverse?
Also, is there anything i can look for as to why itd be leaking with new parts? The sealing rings are new and I polished up the clutch sealing bore with a red scuff pad... I read somewhere they obviously won't seal while dryish so that's why I squirted some ATF on there and it performed much better. I couldn't find any other issues or anything to lead me to believe something wasnt correct so that's why I threw it back together. I got excited lol

i understand the direct clutch is not on in manual first gear, but i thought it came on in when putting into "d" which is where I stall tested.. but am I gathering it still isn't on until it hits the 3rd gear in "d"?

I'll do the reverse stall test this afternoon. Thanks!

 

Not likely, but it is possible. Line pressure is higher in reverse and that may overcome a leak.

Not my area of expertise.

The direct clutch is on in reverse, third, and fourth gears. It is not on in park, neutral, first, or second. Having the shifter in D does not bring on the direct clutch.

 

Just did a stall test in reverse and shot right to 300psi and im seeing the spec to be about 240-290. Does that rule out a bypass/leak in the clutch?

 

Can you watch the gauge while driving? What does the pressure do when it should shift to third?

 

Hopefully the video works as it's a little hard to explain. Has a little pressure spike. Video starts off with selector in drive and first gear

 

If it doesn't work, basically it stays at 100psi from first to second, a little bit after where I feel the 3rd gear should be, it jumps up to 160, slowly falls over a couple seconds to maybe 140, then spikes back to 160

 

That seems to be in the ballpark. I'm going to need to think about this.

 

Im glad im not the only one stumped. Lol thanks for the help thus far

 

Have you checked the valves in the accumulator body? That is the body towards the front of the pan.

 

Hey now, I did a shift kit in a 4R100 a few years back... no third. I had 1/2/4/R. Trans was fine before, I had a valve and spring reversed in the valve body. Not the accumulator body. It may be worth checking that if you drop the pan again. I know they are not the same trans, but should be close enough where it could warrant looking if that far in there.

Good luck!

 

I did the very first time I dropped everything. Itd probably be worth going back over all of that to double check everything.

 

Definitely going to have to check it out as I'm at a loss for other tests at the moment. Thanks

 

I absolutely thought i had my ureka! Moment tonight. Pulled the accumulator body and started pulling valves and springs. Nothing out of thr ordinary, everything was moving and returning. Until I got to the line set... somewhere in my swapping of valves between bodies (my old body bores were a little sticky and I had a spare body to swap all the tugger valves and springs to) i found i had omitted this little guy circled in red in the picture, not sure exactly it's job... I was very excited even though it had nothing to do with the 2-3 circuit, I was excited. Got it all back together, test drove.... unfortunately, still no shift to third. Everything else in there was correct. All the spring colors, retainers, valves.