[EXACTA]

In air conditioning/heating t-stats used in residential homes and commercial applications their is a temp. differential adjustment. This determines how far from the set point it will alow the temp to vary before turning the unit on. In other words if you don't mind the temp variance, one can vary the differential from 1,2 or more deg. away from the set point so the temp can vary away from what you have adjusted the set point to be.

Using the cruise control I have noticed when going up a slight grade the auto. transmission will down shift and the throttle will modulate in order to maintain a constant speed (or at least very close) . Driving the car without using the cruise, one can allow the car to slow down a little while going up a slight grade without downshifting and thus saving on fuel.

What I would like to know (see happen) is how can the cruise control speed differential be adjusted to allow the speed to vary more before forcing the trans to shift and opening the throttle.
Of course this would be something in the electronics that would have to be accessed and points changed. I dont know if it is possible but it seems like it could save fuel.

Anybody know about how to go about finding out about this idea?
Thanks