I would use a Programer for Max efficiency for your driving habits. My 3 level of programing are totally different at different RPM's.
I usualy try keeping the turbo at lower values when cruising and the truck has been very efficient at any speed while towing or not.
My best tool for Effiency has been the scangaugeII that can be used as a MPG trainer, extra gauges, and code reader.
Again yesterday I found that my truck was most efficient on Drive then Overdrive at 50MPH, by as much as 20% better on level 3.
Last edited by caissiel; 03-25-2011 at 07:42 PM.