Hello everyone,
Let me preface this thread by saying that I have read just about every piece of technical info, youtube channel and forum thread regarding this topic and I am trying to narrow down my issues here because I have some very classic symptoms but have verified that most of the things that cause this are not an issue. I will make this as thorough as possible so that hopefully it can help others in the future. I also learned a lot during this overhaul that I would be glad to share.

2004 F-150 FX4 5.4 4R75W trans.

Freshly rebuilt trans with a no overdrive condition

-Original issue was a no reverse condition. Pulled the trans and did a complete rebuild. Reverse issue was caused by the reverse band being worn out and that in-turn chewed up the planetary. I replaced all the normal kit items as well as the planetary and both bands. All servos were replaced and the valve body was overhauled.

-Upon installation and first drive, all went well. Shifts normal, drives great hits all the gears etc. After a day, it began doing the classic no overdrive where it would go into a neutral when it tried to go to overdrive. Of course I immediately thought about the OD band and the servo. Dropped the pan and valve body to verify that the OD band and the servo were intact and functioning. I was hoping to find the obvious servo snap ring broken or the apply pin slipped from the band. Using the servo tool to compress it, I was able to verity application of the band with the servo pressed into the bore by the special tool. I went ahead and went back thru the valve body to clean and verify the operation of all valves while I had it out.

-Put all that back together and still have the same issue. Did a very thorough test drive and verified a couple of things:
1. I do have engine braking in manual 2nd....which means the OD band and servo are applying (which they do in manual 2nd). That eliminates the possibility of a mechanical issue with the band and servo.
2. I can drive ok with the O/D turned off. It shifts so smoothly it is hard to verify shift points but I can achieve about 55/60mph with OD off but it is pulling about 3k or more in RPM. I cannot tell if I am missing 3rd gear or not.
3. I did a test to manually shift from 1-2-D (with the OD switch off) and it feels like 1st is fine, 2nd is fine (but seems limited by speed and rpm) and then when I move to D, I don't feel a "shift" but more of a change in rpm (actually gets higher) but feels as though whatever is holding it back in 2nd is released in 3rd....but there is not a noticeable shift. It is more the feeling of the OD band that is applied in 2nd being released allowing greater RPM and speed. I am not sure what exactly 3rd gear is in the operation of the transmission, is it just the same as 2nd but merely has the OD band released to take away the engine braking ability.
4. With the OD switch in the On position, I can accelerate normally thru 1st and 2nd and then it jumps to a neutral with the engine just revving.

My thoughts. Something is not telling the OD band to apply when its time for OD. I think this because the OD band applies and functions as advertised in manual 2nd. I have a few questions to pose to you all based on that long winded explanation:

-Do you think this is a vale body issue still?
-I did not replace the electronic solenoids on the valve body and there is not a lot of information about them and what they do. Is there a possibility this is my issue?
-Based on my description of my shifting experience am I actually missing 3rd and 4th gear? That would be indicative of some other issues internally.

Please fire away with opinions and advice. Thanks everyone!!

 

This sounds like a problem with the direct (3rd) clutch. In 3rd, the forward clutch is already applied and the direct gets applied to hold the planetary carrier. Then in OD, the forward clutch releases and the OD band applies with direct still being applied. Since you can't feel the 2-3 shift when you manually shift it and it neutralizes when 4th is commanded then the direct clutch is not holding much. Either the lip seal got ripped during installation, the seals on the output shaft are not sealing, or the clearance is not right. There could also be a problem with the stub shaft or splines. The direct clutch is the first clutch pack that is installed when assembling the trans and is under the planetary carrier.

 

I was afraid of that. I'd like to not rip it back out again but if I have to then I have to. Would that also affect the OD or do I have multiple issues going on and the direct clutch may only fix the 3rd gear problem? And by seals you are speaking of the 2 fiber/rubber type seals that you have to slide onto the output shaft and line up in the grooves and then resize? I can see those being an issue.

Any chance of the shift solenoid having a problem? I am thinking no because OD is being commanded, it is just not happening, I get the neutral condition instead.

Great info, thank you for the reply!

 

OD is being commanded. The direct clutch is not holding the planetary carrier. Its possible shift solenoid B is bad but you should have a code for that. You could get a AOD-E test plate and air check the direct clutch. That will confirm if a seal is leaking. How does the fluid look and smell?

 

Fluid is clean and still smells like new out of the bottle. No codes at all. I can have it out and disassembled in 2 hours versus running all over to hunt down and test plate. Just wanted to check and see if there were any ideas of easy fixes while still in the truck. Would a problem with the direct clutch have developed after the first drive? It test drove like a champ the first trip after the overhaul. It was the next day that it stopped going into OD. First night it made a 24 mile trip on the highway here at 60mph or better with no issues.

 

And I have a really bad feeling about those seals....they were a real pain in the butt to install......might have held for a little bit and then blown?

 

Yeah that's what I'm thinking happened. Did you use a lip seal protector to install them or something else? It's easy to roll one and it may not rip until after the first couple of applications. If everything was good the inital test drive then I highly doubt you have a PCM or solenoid problem.

 

Also check for grooves worn in the case where the metal sealing rings on the output shaft ride. Direct pressure goes through there too.

 

Thanks a ton for the advice and the deeper explanation of how the system works. I will just about guarantee I have a rolled seal. I did not have the right installer and bet I rolled them and did not see after re-sizing them. Now that you helped me with a better understanding of the mechanics going on inside it all makes perfect sense. I am off to take it out....again.

This is the 3rd removal BTW. I made a fatal mistake on the first install. I had to buy a planetary set and it came with the output ring gear, sun shell etc. Well I did not pay attention and put the early model ring gear (with the 6 holes) in. That resulted in no OSS reading and instant FAILSAFE mode. It was a simple fix but required pulling the whole thing out again. Lesson learned there.....the ring gear changed in 2004 to let OSS read from the teeth instead of the holes.

Anyways, thanks again. I will post updates later once I get it apart.

 

No problem. The seals I'm talking about are the lip seals that go around the piston in the direct drum. They do not need to be resized. The small seals on the output shaft do need resized once you stretch them to install. There is a special tool to resize them but you could also use the direct drum itself in a pinch. Also check the weld in the drum where the center section that the stub shaft splines into and the drum meet. I have seen a couple break and that will give you the same no 3rd or 4th symptom. They also changed the reverse sun shell for 2004 to have more pulses to the TSS for the electronic throttle body.