[snrusnak]

There are so many factors that effect mpg it's almost impossible to keep it all straight, but the new advertised mpg ratings are supposed to be pretty accurate and you should be able to achieve them with a stock vehicle. I know I get well beyond what my 4.7L is rated for (either 14/19 or 16/19...can't remember). I get more like 17-18/22 but I also have a superchips tuner and am running the 93 tune. Even when it was stock though it got about 16-17/at least 20. 60-65mph is the best speed for mpg, but of course no one wants to drive that slow. If you can hold it at an honest 70mph you should get at least what the sticker says. Also it is true once you have a few thousand miles on the engine it should do better, and winter gas sucks...

I can get up to about 23mpg max all highway at 65mph, but if I go 80mph it's more like 19mpg. That wind makes a difference!

 

[snrusnak]

^I should have stated also that I am in FL and it's ALL flat land. So right now with cooler temps and flat land (and a basically unloaded truck...maybe 20lb total extra weight...mostly in my belly) I have ideal conditions (except poor gas).