Yup...got a suggestion for ya...check out the DiabloSport Predator programmer for your HEMI powered truck.
A link to their website is here:
Enter your vehicle info and check out the tool.
Then, you can contact one of our supporting vendors here (BMC or TByrne) to discuss availability and pricing.
This programmer, combined with a good intake and exhaust installed, is the best bang for the buck mod you can make to your HEMI powered truck.
My truck isn't HEMI powered
but my 2006 Chrysler 300C SRT8 is!
And I can tell you from personal experience the change in how my car runs is awesome. And it's not just about HP and torque. Engine efficiency and fuel delivery can be tweaked. Shifting can be firmed up. You can read, and clear, codes. You can tweak on timing, knock retard, etc....it's an all around tool.
So check it out.
Oh, on the mileage thing??? You just have to learn not to bury your foot to the floor all the time, which is hard when you have improved performance...LOL