I was curious about this also as one of the You Tube reviews clearly shows a blue truck . So went to dealer and they showed me a Bronco in the same color and it looks NOTHING like the pictures above - much darker and kind of dark bluish charcoal. I have never seen a vehicle that can look so...
Did you hand calculate it by chance ? - one of our vehicles has been off as much as 3 MPG from what the trip computer says. (normally high by 1.5-2.5 MPG)