Originally Posted by wedgeheaded
Just to satisfy my own curosity, I filled up with 89 the last 2 tanks. With 87 the best I could get was just a tad over 15MPG. Last fill up using the 89 I got almost 16. My trip computer has shown as much as 16.8 while driving. I had been wondering what effect the ethanol, that they put into the gas during winter, has on it's octane rating. I tried it just for giggles and was pleasantly surprised. I know ethanol has a lower flash point and would bring the FP of the gas down with it. It might be such that my truck just likes the 89 better too. I know octane has more to do with CR than anything else. Anybody have any insights or thoughts?
isnt a tad over 15mpg and almost 16 mpg pretty much the same!!!