Having owned 2 previous 4-Runners as well a 2001 Tundra, I knew the gas mileage wouldn't be great. Coming, most recently from a Subaru CrossTrek that regularly got 30 mpg, I decided to just bite the bullet and enjoy the 4-Runner for its great attributes and to heck with gas mileage. So...I'm pleasantly surprised with my early results.
I live in SW Virginia, just a mile or so off the Blue Ridge Parkway so HILLY terrain. My first tank was 18.3 followed with the 2nd of 19.05. These were all 2 lane mountain roads with very little traffic, varying speed, typical break in type driving. The third tank was 80% interstate at 65 - 70 mph. Couldn't be happier with my Fuelly results of 23.0 for that tank and an overall average for the first 900 miles of 19.8. I was prepared for something more like 17, maybe 18. Jim happy.