Just researching. I know these trucks aren't built for gas milage. So here is the break down. I want to give it a little more options. I have 275/65/20 and it was scheduled to have 18 series tires per manufacture. I m curious that I have to get the maps changes due to tire size. And was also looking at a CAI as well as new air flow meter and pedal commander. I understand that it won't Increase torque, just looking at fuel and some hp additions. Besides a tune up which it's coming due for. Any suggestions and I get that I may have to pay a few bucks for good tuner and not one of the light flash plug and play for under $100.