im no tundra expert, but there is always a more efficient way to have any system operate
what makes tundras get less mileage, lets start there(dont pay attention to the obvious ones like the V8 and 4x4)
1. running bigger tires- is it because, there is more mass in the bigger wheel than stock?
maybe a lighter wheel may do the trick?
Or is it the size of the rim, going from a (17'' stock?) to a (20 aftermarket?)
2. bigger tires and tread pattern?
3. does lifting you truck- A. with suspension lift? B. body lift?
4. exhaust and intake systems- this is a question for the guys that have a dyno available- diameter of exhaust tubes? and X pipe V.S. Y Pipe system? and intake piping with a cone filter?
keep in mind folks, im just throwing these questions out there to organize the answers.
add more questions and theroys