More ethanol sucks more gas period. I think about 1/2 of the increase in mpg might be due to the increase in temps say 10 degrees winter to 50 degrees now. Cold sucks more gas than higher temps.
I once ran E85 on my tundra and chevy silverado and got 13.5 hwy mpg vs. 17 or so normally. If it ever warms up here in the next few weeks, I hope to achieve 1-2 more mpg as well. I'd love to be able to get 21-22 hwy mpg and should, but the politicians are in bed with the oil mfgs.
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