Hey! How's it going? My name is Jonah and I recently got a 2005 Yukon Denali XL. Long story short, I;m not new to forums and frequent F150Forum.com. My dad just got a 2012 F150 and I was the recipient of the 05 'Nali. And let me tell you, I'm one lucky guy! My yukon has the 6.0, a factory custom paint color, and all the other Denali bells and whistles. I just ordered A Spectre cold air intake today in hopes of better throttle response and mileage so I'll run some tests and well see how I do. Im averaging about 15.7 MPG right now. My ideal set up is to get the Denali to arounf 380-400 horse and try to squeeze out 18 MPG. Thanks for welcoming me to the forum in adnaced and enjoy your GM's 