5R44E or 5R55E? Inquiring minds etc., etc.

[olddude55]

My '03 Ranger (2.3L Duratech, 5-speed auto) is suffering from the typical tranny issues: 2-3 flare, flashing O/D light.
Problem: Which tranny is it? According to the ID chart in the Tech Library here, transmission code "D" on the door sticker means 5R55E, but also according to the ID chart, the 5R44E was used with the four-bangers and the 5R55E with the 4.0 six.
Is there another way to ID the transmission? Do both trannies use the same valve body?
And how can I pull the tranny fault codes? My neighbor connected his scan tool to the diagnostic plug under the dash and found no codes, but I don't know that his tool will read transmission codes.

 

[exbass94]

4 cyls have the 5r44e. The flare is typically caused by a bad valve body gasket. Replace the gasket, torque the valve body back down, and see what happens. I don't know if it's the same valve body as the 5r55e.

 

[olddude55]

I thought Ford had this problem solved by 2003 (my truck was actually built in October of '02), but apparently this isn't the case.
Looking at two shift kits (Transgo and Superior) right now, or an entire reman valve body with solenoids. If I'm going to tear into this thing, I'll likely replace the EPC solenoid at any rate.
I've rebuilt motorcycle engines, done a lot of different stuff with cars (brakes, suspension, fuel systems), but never an auto tranny.