After one thousand miles in my 2017 Limited, I'm disappointed in the highway mileage since I hypermile as much as possible. I can't get ANYWHERE near 37 mpg on a 200 mile trip....and I may have discovered why..... In automatic mode, cruising at 50mph, I noticed this morning that the revs were at 2000 rpm....seemed high....so I switched to manual mode and saw that the car was cruising in 5th gear at that speed. I then shifted it to 6th gear and it dropped to 1500 rpm..... which means, in order to hypermile, it needs to be in manual mode! Lesson learned!