I did some checking on internet about the Ecoboost engines and at least some people are saying that they need a major valve/head cleaning at about 80,000 miles due to poor performance. There are photos showing the gunk build-up. Costs about $800 to clean-up. I calculated I would save about $800 in gas over that time so it would be a break-even cost scenario, but there would be lost time getting it to the shop and out again. Maybe these folks run cheap gas or something however, I did not go into great depth on the situation, especially since the Ecoboost ended up not being available on my 2017 SWB XLT Wagon anyway. I could swear it was available on the 2016 however. Anyone seeing this gunk build-up at 80K?