Hello everyone. Just purchased a 2017 Mitsubishi Mirage GT. I've been driving a friend's 2017 G4 Mirage basic trim and was seeing 40ish MPG while traveling 70MPH but I'm only barely gettinf 34mpg. Theirs has approximately 12k miles on it. We both have CVT's

Under the same driving conditions shouldn't I be getting the same mileage? Is this due to engine break-in period? I'm hoping I didn't make a poor decision as the Hatchback version was shown to have superior mpg than the sedan