Just turned over 3,000 miles on my '18 Denali 252 HP.
Averaging 28 on the road. On two trips I exceeded 31 on favorable wind days, so i figure i was averaging 30 mpg.
That's incredible. My Acadia that i traded in never averaged anything more than 20 on the road.
I've been using premium gas on the highway, but may revert to regular for suburban/city driving. I was in the 2 wheel drive mode during this period. I turned on AWD during a driving rain storm and noticed the gas mileage was 3 mpg less.
Last edited by cincyterrain; 05-07-2018 at 01:32 PM.