Okay. Home from OBX. Read out says 15.4 on the way home, which tends to be a bit conservative. It said I got 15.7 on the way down but I hand calculated when I filled up and it was 16.0 on the way down. The trip back was straight cruise control except about 20 mins of idle, brake, idle, brake through some roadwork.
I was doing the speed limit except for the 3 major slow downs. It was 70 for most of the trip. Then varied between 55 and 35 changing every few miles for the last 80 miles or so. I have been a 6.5 hr trip but took 9.5 hrs. We were going to leave tomorrow morning. I'm leaving ahead of the rest of the group and heading back tonight. I shouldn't have much traffic but I usually got better mileage on the way here than on the way home in my 1500. I'll post my results.
A lot of it is where you are driving. I am in MD and we have a lot of hills. My 1500 averaged 14 MPG lifetime and I could get 16 or so just driving highway around here. Again, even local hwy is up a hill down a hill, rinse and repeat. Now taking a trip to OBX every year I got 22mpg down and back every year. It's a pretty flat drive.