Hauling with and towing a U-Haul

[GCross762]

I believe you meant 87 octane. 87 octane is the minimum recommended, and you should never use lower octane fuel. At many higher elevation locations 85 octane is "regular," with 87 or 89 the mid-grade. Don't use 85 octane--stick with 87 octane or higher.

I agree with you that the lie-o-meter should not be trusted to deliver accurate mileage stats. The change in indication from roughly 19 mpg to 23 mpg is a perfect example.

I'm going to make an assumption here (please tell me if I'm wrong): The weather was generally warmer for the three tanks of regular vs the three tanks of premium. In my experience with EcoBoost engines cold weather has a far greater impact on fuel economy that fuel octane. If the weather was significantly colder for the three tankfuls of premium that could explain the reduction in fuel economy.

It's not surprising you felt a difference in performance with premium. Being more performance oriented, members of the EcoBoost Mustang community did a lot of dyno testing, and most estimates place the difference in engine power output between regular vs premium gas at 10%-15%. The 2.3L EcoBoost was rated at 310 hp on premium, but dyno testing showed that number was closer to 270 hp on regular. The 1.5L in the Bronco Sport makes 181 hp on premium fuel. A 15% reduction would dial power back to around 150 hp. That would make a significant difference in seat-of-the-pants feel in the mountains!

Yes to the Octane level. The temps of the day were with in 6 degrees of each other. Due to my driving i can do 1000 per week. Now that im back on regular gas and well after my testing yesterday’s temp was really high it was at 47 degrees and on the way home i got over 31.3 miles to a gallon. Lieometer said 32.7 so i filled up again to see if i was dreaming. I did get better fuel economy. Cant wait for summer to see how high it goes.

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