I'd make a proper diagnosis first instead of throwing more parts at the problem. If the torque converter is staying locked, it should be pretty apparent from monitoring your tach. Here is a recent thread on that issue.

 

It doesnt sound like thats my problem. The trans shifts pretty normal and when the loss of power occurs such as when i get to a hill and the motor has to pull, the trans downshifts normally. Im thinking now that it is either something with the injectors or the fuel pump module that people have had problems with. Beyond that i have no clue.

 

Austinbf150

My 06 Lariat is doing the exact same thing as yours, Hopefully by now you have figured out the problem, do you remember what it was?