Hi all.
I have a 2006 4R75E installed in my vehicle (2006 Crown Victoria Police Interceptor). While not a Ford truck, it does share the trans, and am really hoping to be able to pick the brains of people more experienced than myself.

The transmission in my vehicle showed itself out originally by losing 3rd gear in a downshift from O/D, neutralling out. I drove it only to the shop I work at, and proceeded to weigh the options. I have since learned how to rebuild it, replacing all clutch packs, and following factory service manuals to get each within factory clearance specifications. I air-checked along the way, and each clutch pack leak tests properly, with no excessive air leaks.

I also replaced the forward drum, direct drum, all lip seals, EPC solenoid, and purchased a valve-body from a business owner with a good reputation.
The case has wear marks that I did not like and also replaced that. Front Pump and torque converter are new, teflon seals on the input shaft, shift solenoids, torque converter lock-up solenoid, etc. It would be a shorter list of things that have not been replaced.

The problem that I am facing now is the car will drive completely respectably, holds torque perfectly, no slippage, and shifts exactly as expected until the transmission fluid temperature reaches 180 degrees Fahrenheit. Then, the next time you are stopped and pulling away in 1st, it will shift 1-2 poorly. It feels as though it takes pressure out of the forward clutch and does not apply it and the intermediate clutch as designed. Occasionally it will pause power output for up to 3 seconds, then will re-apply and feel like the car has been lightly rear-ended.

I have checked over what I know to. The check ***** in the valve body are new. After the poor shift, even if the temp is still above 180 degrees, it will continue on as normal. Then it will do it again at a later time, sometimes in the same drive.

I hope someone has experienced what I am. I have been dealing with issues on and off with this situation over the course of 6 months, and feel it would be poor judgement to call it a loss and order a transmission online that is just as likely to give me a different or similar issue.

Thanks in advance - jk

 

DId you check the basics? Fluid level (checked warmed up, in park, engine idling) and check for codes in the PCM?

 

I have. Fluid level is good (within the crosshatched area on the dipstick) at 170-175 degrees while idling in park. No codes in the PCM, no flashing O/D light or anything of the sort.

 

Not certain there is a pressure port, but have you checked pressures?

If the filter is not installed properly, it will suck air and hydraulics does not work well with air in the system.

 

There is a pressure port.

It is on the driver's side of the trans, towards the front, just above the pan rail. It has a black hex head plug from the factory.