Quote Originally Posted by stchman View Post
Does your 2010 have a manual shift mode? If yes I've read that putting the truck into M5 will not engage AFM.

Most tuners will disable AFM, Hypertech, Diablo, etc.

Turning off AFM will really impact your gas mileage.
I've read posts by many that turning AFM off does not affect mileage that much.

Like your truck...