I took another trip, this time much longer and with more gear in the back of the GX. Also my config changed just a bit, I removed the Front Runner roof rack and installed Rhino Rack cross bars, but still have the James Baroud RTT, and I installed the Icon coilers to lift the vehicle. I drove 2,355 miles and averaged 16.9mpg. For the days I dove all highway portions I maxed out at 19.8mpg and for the days I did mostly trails I was at a low for the day at 9.5mpg. If I average the days I did mostly highway miles I got an average of 17.5mpg.
I think going from the Front Runner to the Rhino Rack brought back some of my highway MPG. I was driving higher speeds on the highways than I did when I had the Front Runner, but appears that I was getting better MPG. (all MPG is via my
Automatic OBD II device, which I would no longer recommend due to the fact for new users they went to a subscription service).
For the spread sheet, my truck is a 2012 and I still have the Cooper Discover A/TWs.