2012 Ford F-150 Lariat 4x4 EcoBoost Long-Term Update 1

One of our biggest questions about the EcoBoost engine in the F-150 is whether the EPA numbers will hold up when it comes to real-world driving. We used the truck's driver information screen to keep a close eye on the fuel economy during the daily commute to the office. When you have one of the trip odometer screens up, one of the other details displayed is average mpg. Because I am so curious about the EcoBoost's fuel economy, this is the first truck I've ever driven with a fuel-economy screen that holds my attention like the display in a Prius.

At first, it seemed like the F-150 wasn't living up to the EPA's 15 city/21 highway mpg numbers. On the screen, the average mpg showed numbers in the low 14s around town. Uh-oh. But as time went on, the average miles per gallon improved. I found that during my daily commute to the office, economy was better going there than it was driving home, presumably because I was going downhill a bit on the way there and up the same hill on the way home. When I took a longer trip, though, fuel economy improved beyond my expectations: I saw 21.5 mpg on the "average fuel" gauge, and the fuel economy for that tank was above 18. My commute is almost entirely in traffic, so it'll take more highway time to get a fairer look at the overall economy. However, I do wonder if the EPA's drive evaluations include sitting in stop-and-go rush hour traffic with the air-conditioner on, because that's my real-world daily experience on the way home. I also want to find out how much fuel economy suffers when towing, and that's something we'll explore in the near future.

I have another fuel-related question. When we've seen data for vehicles powered with the 3.5-liter EcoBoost engine, the specification charts would say that the engine was designed to run on 87 or higher octane fuel. However, "For best overall performance, premium fuel with an octane of 91 or higher is recommended." What does that mean? Ford didn't specify a difference in horsepower or torque, so for the duration of this long-term test, we're going to run the truck on regular unleaded and base its performance on that, both at the track and on the road. So far, the truck has performed flawlessly on 87-octane fuel. It's very quick off the line, and power delivery is smooth.