The fj is rated less probably because it weighs more. The taco has the same power train though. Don't expect good unloaded mileage with that 4.0l. Our 09 Tacoma was thirsty and never saw over 20 mpg. Towing locked in 4th per the manual had us at 3k rpms and 8 or 9 mpg.
The f150 has better mileage, and an extra gear to keep those rpms down and mugs up. Just about any makers truck would be better.
2012 Koala 25DS
2011 F150 Ecoboost SuperCrew with Max Tow Package