Sounds like a frt pump seal or converter O rings. If the prob happens after it warms up is it over filled ? If the fluid gets hot it leaks out of frt seal is common.

 

Sadly, the leak occurs 10-15 seconds after start-up. I wish it would be an issue only with it's hot. Sigh. All of those seals are brand new, as a part of my rebuild. It being overfilled is also out because it leaked when it only had 2 gallons and the capacity is around 4. I appreciate the insight though. Frustrating.

 

Yo robothegreat,
Here's the 96 Bronco Workshop Manual, partial @ 1996 Bronco/F-Series Workshop Manual

Perhaps some info in following can help:

See Fluid Leakage in Torque Converter Area, etc @ 1996 Bronco/F-Series

Torque Converter - Leakage Check @ 1996 Bronco/F-Series

Disassembly/Reassembly of Subassemblies @ 1996 Bronco/F-Series

 

Yo robothegreat,
Here's the 96 Bronco Workshop Manual, partial @ 1996 Bronco/F-Series Workshop Manual

Perhaps some info in following can help:

See Fluid Leakage in Torque Converter Area, etc @ 1996 Bronco/F-Series

Torque Converter - Leakage Check @ 1996 Bronco/F-Series

Disassembly/Reassembly of Subassemblies @ 1996 Bronco/F-Series

Awesome! Thank you for the helpful resources. Hopefully I can find some solutions in these.

Edit: That shop manual is absolutely amazing. I can't believe I've been working without that exceptional resource. Thanks again!

 

I found the issue! I did have to remove the transmission for the third time. The problem was:
A bolt which attaches the pump to the case had been stripped out and was not properly torqued. I replaced the damaged helicoil with a larger new one (M12) and used a M10 bolt which barely fits inside through pump... I also drilled out the little crush washer very carefully so I could reuse it to ensure a leak-free seal. I also added a small amount of Rite Stuff by Permatex to help it on the washer.

 

Also I fixed two more issue and I want to share in case someone else has a problem.

1) The transmission was not engaging in forward or reverse gears. I fixed this by revving the engine and letting it sit at various RPM for quite some time (15-20 minutes of idle). Eventually, it went into gear and worked perfectly. I have since driven it and it's great now. My belief is the various passages needed time to fill with fluid. I feel good about this theory because when I performed the fluid flow test (disconnected the line going to the trans cooler), lots of tiny bubbles were present. Acceptable flow is 32oz (1 qt) in 15 seconds, which mine had thankfully. Who really knows. I am just happy it works.

2) The transmission would not shift past second gear. I fixed this by readjusting the shift linkage. I would also check the MLPS. I followed the directions found here: http://www.diesel-dave.com/vehic/manual/stj/stj75018.htm
I used a small 3-lb hand-weight, two cable ties and some tape to secure it onto the lever. The engagement is perfect and it shifts amazing now. The issue was it was adjusted too far forward, hince the MLPS would just think it's in "2" inside of "D" and limit the shifts to first and second gear.

Again, thanks miesk5 for your help by linking that shop manual. Such great resources.

 

I wanted to share more information in my E4OD-saga. I hope this information can help someone. I'd love to help anyone struggling with this transmission, so please reply if I can help provide any information.

The short: I had a stuck 2-3 shift valve in my main valve body which prevented the transmission from shifting past second. I removed and cleaned this stuck valve, and everything works perfectly now!

Two weeks ago, I went on a 80+ mile journey to a really nice off-road trail in North-East Georgia. The transmission did awesome, and the 4WD was exceptional, even with open diffs and 31s...

Somewhere along the way on the trail, the transmission quit shifting past second. It would shift perfectly fine into second then just rev endlessly...no third or fourth gear. I was able to still enjoy my day on the trail and drive to a parking lot after. However, as my journey home required lots of interstate, and I wasn't comfortable doing 35mph at 3000rpm, I left the Bronco and came back later with a trailer and towed it home, not the ending I was hoping for.

Later at home, I did the following (I recommend these steps if you are having similar issues)
1) Checked solenoid and MLPS connectors for moisture or damage (nothing of notice)
2) Checked the resistance values of the shift solenoid (all values within spec)
3) MLPS was giving me some anxiety, so I'll admit I threw parts at it and replaced it (issue still persisted)
4) I removed and cleaned the, about 1 month old, VSS (issue still persisted)
5) I measured the resistance of the Throttle Position Sensor (TPS), and the values were out of spec, so I replaced it (issue still persisted)
6) [SOLUTION] Finally, I removed the pan, main valve body and found the 2-3 shift valve was stuck in its bore; I simply touched it with my screw-driver, and it sprung back into place. I also removed it and cleaned it and checked for other damage. I reassembled everything...This INSTANTLY fixed the issue. It now shifts perfectly. See attached pictures for Help. The red arrow points to the 2-3 shift valve. Make sure to only take one valve body sub-assembly off at a time (main or accumulator or solenoid pack, NOT more than once at once) so that the check balls don't fall out. Also, leave the stiffener plate. I recommend starting all bolts with your fingers to avoid stripping out the soft aluminum case.

So, yup. Check your valve bodies if this issue exists.

 

Was going to say a check valve may have wear in the bore or valve. This guy has some good videos on 4r70w bore repairs. Depends on the transmission model's common problems though. THIS IS YOUR TRANSMISSION
e4od Transmission Bench