so what chip or programer do you guys suggest for mileage. its for a early 99 F450 5 speed with a 12ft work bed that wieghs about 10,000Lbs (whole truck) i straight piped it 4" and now it gets 11 mpg and the S&B intake should be in soon. it doesn't have a hitch and never will so towing isn't a factor. any ideas?