Originally Posted by ErnieT
Just wanted to throw this out there. Since installing this a week ago(w/ dp back exhaust), Im averaging approx 3-4mpg better so Im a happy camper.
It seems the higher tunes are actually better for fuel mileage as long as your foots not in it, lol.
Not to burst your bubble, but are you doing hand calculated fuel mileage?
Any time you "tune" one of the Power Stroke motors, the on-board mileage computer always shows way more MPGs that the truck is actually getting, at least that's been my experience on the 7.3s, 6.0s and 6.4s that I've owned.
My current 2010 F250 with 3.55 gears & Spartan tunes will get from 12 to 12.5 mpg in City driving and 18 to 19 mpg at 70 mph on the Highway. The truck's computer typically shows 16 mpg in City and 23 mpg on the Highway.