I easiest way I can describe how to save fuel is:
*practice driving as if you have no brakes.
Try not to use engine braking also.
One can pop the tranny into neutral and coast with the engine idling. Be safe.
The point is the further you drive ahead, the more you can save.
Because aero-drag increases exponentially with speed the best mileage is often just above the speed where the tranny stays locked up in high gear.
Keep in mind that overdrive is great as long as the converter stays locked.
If the load unlocks the converter in overdrive, then you may gain efficiency by going to direct drive locked converter. Two reasons for this the tranny gear train is often more efficient in directdrive and when the converter unlocks you lose some of what you gained with overdrive.
On my wish list are changes with the factory cruise controls, there has got to be a better way. When the + is pushed the vehicle should accelerate at the most efficient rate, not unlock the converter or down shift. Also tuners, I would like to be able chose a wider band width at a set speed. For example, Allow the car to go 60 down hill and 50 uphill if the operator choses. Cruise control should strive to keep the engine in closed loop.