ok guys im completely new to the cummins scene. ive had an 03 ford with a 7.3. and looking for a 06-07 dodge mega cab 4x4 dually with the 5.9. i know with my ford, you had the off the shelf tuners and chips that were ok but you also had the custom chips and tuners that were a lot better. what is the best route for the 5.9 cummins? im not looking to make it a race truck. just add a little power and mainly fuel mileage. i know there are off the shelf tuners for these trucks but are there custom ones that are better? thanks again for the help!