...after owning 2 Tundras it’s more than 1 or 2 mpg difference between Ford, Ram and GM and the Tundras I owned. I couldn’t get 19 or 20 mpg out of any of my Tundras, the F150 Eco and Ram Hemi can. 15 was pretty standard on a highway road trip in the Tundra with nothing hooked to the back of it. 4+ mpg is a big difference in economy on say a 500 mile trip. And don’t get me started on Tundra mileage hooked up to any trailer regardless of weight, suddenly your luck to get 10mpg.
That's been my experience with my 2000 Tundra 4x4. 11-12 mpg around town--maybe 13-14 on highway. Wonderful truck otherwise.