Has anyone tried using an after market programmer to increase performance & fuel economy on their 5.4 liter expedition? I am changing all my fluids over to complete synthetic and was considering reprogramming the trucks computer as well to enhance performance. Any thoughts or experiences would be a great help!
Thanks!
ED.

They do work and work well, I would go with a programmer, stay away from the chips. Chips are more prone to cause you problems. I would recommend looking into Bama Chips. For a Ford vehicle, I have not seen anything better.