5R55E Locked or Stuck wont go out of Park 2000 Mountaineer

[Mark in VA]

Hello Ladies and Gents, I have done a search and reading and now I am Looking for troubleshooting and diagnostic ideas before I start swapping parts. What are my next steps?

Here is what it is doing - the transmission does not "go into gear", the shifter lever and linkage move and the lever on the side of the trans case moves freely and 'clicks' into all PRND21 positions.

The driveshaft will not turn in any shifter positions, which I describe as the transmission itself locked or stuck on Park.

it is a 2000 Mercury Mountaineer Eddie Bauer AWD 4.0 V6 240,000 miles, about a year ago reverse gear went out - everything else worked fine. I swapped in a 'supposedly rebuilt' transmission that I ordered online from a transmission re-manufacturer. He was out of state, I don't remember who.
Due to life / weather / a dead fuel pump, the truck has sat idle for a year until I just got it running again last week.
Once started, it had a blinking OD light on the dash and the OBD scanner showed code P0705, bad transmission range sensor. I Replaced the TRS switch and we have no codes stored now.

Here is what I know:
Rebuilt ? transmission
New Torque Converter
New TRS switch - Engine starts with the shifter in P and N, reverse lights turn on in R
All electrical connectors are plugged in.
Engine runs good, and after several minutes everything comes up to proper operating range temperatures.
A.T. Fluid level is good, per the dipstick after adding 9 to 10 quarts of Mercon V.
Fluid flow is good through the cooler is good, I opened the upper (return) cooler line to start the flush process
The parking brake is not frozen, the Rear wheels will turn if I manually shift the transfer case to N.

Line Pressures at the test ports are good, and change (increase from 60psi to 120psi) with shifter position change to R.

Thanks for your consideration and thoughts - I open open to all ideas

 

[JK080]

From what you say in your post tells me you have ruled out pressure, linkage, electrical so the only thing that comes to mind would be the mechanical operation of the parking components. With the pan off you should be able to see the shifter shaft, detent gear, nut and some of the rod going back to the parking paw, if the rod is moving with the linkage the problem could be with the parking paw itself, maybe due to a assembly error. At that point I would remove the transfer case and adapter off the back of the transmission to get to the parking gear assembly to see what might be going on.

 

[Mark in VA]

Awesome thanks for the direction, James. I am able to work on my cars only outdoors when weather permits, so updates will come at a low frequency.
I dropped the pan and found a steel pin, It has broke off from the inside manual valve lever - so this transmission has not been changing gears internally. There's no telling what gear it is in.

How much dis-assembly is required to replace the inside lever? It looks like it is held on by a big nut about 20 or 22mm.

 

[JK080]

You will have to remove the large nut to get the detent lever off the shifter shaft, you may have to remove the roll pin that is located in the pan rail of the case to allow the shifter shaft to move back far enough to allow the detent lever and rod to come out.

However this problem you found won't have anything to do with it not coming out of park. This problem creates issues like no engagements or only having a drive gear or just reverse, just wherever the manual shaft happens to be. Park is operated with the rod that goes back through the back of the case to the parking paw and parking gear.

At this point I would confirm that it truly is stuck in park. Make sure the linkage of the transmission is out of park and see it the drive shaft turns, if it still does not turn you will have to dig deeper into the parking mechanism to see why it wont release.

 

[Mark in VA]

Now I believe I was mis-diagnosing the symptoms of mechanical failure. The parking pawl mechanism is working correctly and the transmission output does turn the driveshaft. Sorry to lead you down that path.

I have forward gear in L2 and L1 but nothing in Reverse or Drive. Should I automatically assume a broken OD / Input sprag?
Anything else to test before pulling this transmission?

Changes since my last post - Up to now:
I removed and replaced the broken manual lever and the valve body.
I chose to do the VB because when I dropped the pan , the manual valve on the Valve body didn't feel like it was sliding smoothly, so I replaced the valve body with a rebuilt one.
New gasket, checked (ohms) the solenoids, new reverse servo O-rings, torqued the VB bolts to spec in the proper sequence.
I put in a new transmission filter, and pan gasket, re-filled the transmission with about 6-7 quarts, per the dipstick - running in Park.
Pressure test at the line port is correct, and changes when shifting from P to R to D. But - no gear in R or D.
No codes in the computer memory, no lights on the dash.
The O/D OFF light does turn on and off by the switch.

Thanks for your consideration and assistance.

 

[JK080]

Yes only having manual low and 2nd is a symptom of a failed input sprag. At this point there is nothing left to do but pull it out and take it apart. One thing for sure something is broke.