Hi all. I'm sure this question has been thrown out there, but here goes (again). Are the performance chips that are available worth the cost? I have a Ford F350 6.4L Diesel and I am looking to improve the mileage. I have friends with other vehicle makes and models who have the performance chips and swear bu them, BUT they have them for other reasons than I am looking at (they like to go FAST). Anyone have a chip and do you find that it helps??
