Found out what my "B" code tranny means from a spec sheet I downloaded from Ford when I bought the truck new, forgot I had it. The "B" code means: "4-Speed Automatic Overdrive (4R70W)".
Now I did find this info as well, just to through some confusion in there
Transmission Code B on a 2004 F150 is a 4R75E transmission. It is a 4 speed Automatic (AODEW).
Description found on Truckworld.com a review:
"Another improvement in the drivetrain is the use of the new 4R75E 4-speed automatic. The 4R75E is an evolution of the 4R70E that is used in the current F-150. The biggest changes are a faster computer, redesigned toque converter, addition of a turbine-speed sensor, "smart" shift control unit, and a fully sealed case filled with lifetime transmission fluid."