OK, I just came back from vacation, and for the first time in years we drove to our destination. I drove from NJ to FL and back. I forgot to do mileage on the trip down, but got it on the way back. My results are interesting, to me anyway.
2016 Colorado LT, 4x4. No towing, maybe 125lbs of cargo, and 370lbs between my self and my wife. Truck is bone stock with the exception of a tonneau cover. All gas purchased was middle grade, 89 octane. There wasn't really any major traffic issues on I95. There was some rubbernecking in Delaware for about 6 miles. Average speed, I would guess to be right around 65. I was afraid my hood was going to blow off if I went over 70mph. Yes, the hood flutter is a real thing and needs to be addressed.
Fill up #1
DIC Reading ~ 23.3
DIC ~ 23.7
DIC ~ 24
DIC ~ 24.8
The DIC fluctuation is the most surprising to me, then the lack of getting to 25MPG. It's a truck so I wouldn't expect much better than what I got. I didn't buy it for economy reasons. Something else I noticed about the DIC. When I fill up normally, my miles to empty starts out at roughly 390. While on this trip, my miles to empty jumped to 480 on fillup 2 and 503 on the 3rd fillup.