HI, I have a 03 F150 5.4 and I am looking to try and get better gas mileage.
It was suggested to use a Predator Programmer u7153.

Will this help or do you have any other suggestions?

 

Programmer may or may not improve your gas mileage. As you've probably read the Gotts Mod is the first choice of many. I've got dual exhaust, K&N CAI, Edge CS Programmer with custom tunes, E-Fans, and Underdrive pulleys. I usually get about 14mpg with the AC running all the time at almost full. I however also suffer from L.F.S. (lead foot syndrome) and with each improvement there is a noticeable difference in power and torque. I also carry 400-700lbs in the bed at all times. Easiest way to get better gas mileage in a truck is regular maintenance and be easy on the gas pedal. If it still isn't enough, then buy a prius.