5R55W No 3rd Gear, out of ideas

[mikerace15]

I have an 02 mountaineer 4.6 AWD with the 5R55W. Vehicle has no 3rd Gear and gives the codes P0733, P0734, and P0745. Despite the 734 code the truck will eventually shift into 4th. So far I have checked the following:
Adjusted intermediate band: was able to torque the adjuster to 120 in-lbs to the band is not broken.
Checked solenoid pack: Removed solenoid pack from trans and all pins ohmed out correctly, also checked screen for blockages and none were found
Removed intermediate servo: I pulled the intermediate servo and it was intact. It looks like a bushing has already been installed in the bore. I don't see any obvious wear, is there a spec for the diameter of the bore so I can measure it?

At this point I'm at a loss, if its not the band, solenoid pack or servo, what could it be? Am I missing something in the diagnostics I have done so far? Any help would be greatly appreciated.

 

[JK080]

I had a Mustang not long ago that didn't have 3rd gear, I dropped the valve body and air checked the servo through the case, the band was a solid apply so I replaced the valve body with one off a core and fixed it. I didn't see anything with the valve body that was obvious or might keep 3rd from applying but replacing it fixed the car for me. The valve body is still on my table because I still would like to know what is wrong with it, I just haven't had time to investigate.

Air checking the trans in the car is messy but it might be where you are headed, if it checks out I would look at the valve body, if you dont see anything you might want to replace it.