A 14 bolt pan would indicate an old style AOD, which has not been in an F-150 since 1993.
The E4OD will have a 20 bolt pan.
The AODE/4R70W will have 16 bolts.
The AODE and 4R70W are identical, except that the 4R70W has a bolt pattern to fit the newet 4.6L and 5.4L modular V8's not found in trucks until '97.
Your truck will have an AODE or an E4OD, with the latter being much more common.