SORRY! lol forgot to add what kinda truck I have. 1993 5.8 4wd e4od

Truck will drop gears. Pick back up to original gear, neutral drop.(any sequence it doesn't do this in this order Everytime. Sometimes it neutral drops sometimes it doesn't). It's getting worse the more I drive it. Fluid good, correct level.

Engine has fresh rebuild, transmission was built less than 3,000 miles ago by a reputable shop. No codes, over drive light does not flash, tried a different instrument cluster (just incase the Module in the cluster was bad) new ford speed sensor, new MLPS, and new solenoid body (warranty from the trans builder). When the new solenoid block was put in, pan was checked for debris, nothing found. Pan super clean, fluid clean.

Before I go all out and have to send the transmission back to the builder. I wanted to go over the truck and make sure I didn't miss anything.

My plan is to check line pressures and also to check the speed sensor ring in rear end. And I'm going to check the wires while driving the truck to make sure I'm not dropping signal while driving.

 

any ideas guys? Just trying to make sure I didn't miss anything.

 

I have seen the neutral safety switch cause these type problems in the past. Just an idea from your description.

 

If it's not internal to the trans itself, the only things I can think of that you haven't changed is the RABS module behind the glove box (tied in to the speedo), the speed sensor on the trans (or maybe it's on the transfer case with your 4x4) and the computer itself.
The cruise control is tied in to the speedo as well.
I don't know if any of those could cause your problem, but they are tied in there.
Also, as an afterthought; presumably you're trying to eliminate all other possible causes before you throw that trans back at the rebuilders, so I guess it's worth mentioning that a wrong signal from the TPS can cause shifting problems, especially in the E4OD it seems. Usually doesn't cause your symptoms, but it is tied in to the shift signal in the PCM.

 

I haven't tried the RABS module yet. I have tried a new output shaft speed sensor (tail shaft of the transfer case). The cruise control works as it should. I know that doesn't mean anything. I just wouldn't know how to go about diagnosing it. The truck has a newer TPS on it, due to another concern earlier last year. Again doesn't mean it didn't go bad lol. But as you said I've never known the TPS to cause these kind of symptoms. I'll see if I can locate a RABS module just to try. I got the full diagnostic wiring schematics today. I Also grabbed my pressure gauge and multi meter from work today. So I'll keep this updated for just the sake of having the info out there, should anyone have these same problems (God forbid because this sucks)

Edit: it could very well be internal to the transmission itself, I'm just trying to make sure it is before wasting anyone's time.

Thanks for the replies guys, I appreciate it.

If anyone has any other ideas please throw them out there.