Chance, I agree driving style comes into play along with using the tow feature. Without a tow I was being more cautious in acceleration. When you are getting passed by a tractor trailer then you know you need to step on it a little more.
I would try to auto shift below 3000 RPM and cruise I think was 1900-2100 RPM. Using the tow feature seems to get a lot higher RPM's on shift up and also the engine braking on downshift increases fuel consumption. I agree with you driving style, terrain, weight, etc can effect economy.
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