Reprogramming shift points

I have a 2.7 cyl with automatic. I believe I can improve my gas mileage immensely if only I can get get the transmission to shift into 4th gear earlier. As it is, it shifts into 4th between 35 and 40 mph depending on load. Problem is, the speed limit in the city is 30 and even at the flow of the traffic of 33 to 35 the truck rarely utilizes 4th gear. Is there a reprogramming I can do to remap the shift pattern. Where I live I do not have the benefit of driving much faster than 35 most of the time.

 

nope

 

my god i wish that someone would figure out a way to do this. I hate that my truck shifts into 2nd gear immediately when I'm pulling out into the street and the it drops back into 1st when I need to go quickly...I shift it manually most of the time because of this...