In my opinion always a tough area to discern what is good MPG due to so many variables.
1. Driving habits: Do you accelerate hard or lightly
2. Speed: Goes without saying
3. Tires: Tire size, type, aggressiveness of tread and height profile all impact engine output and ability to roll
4. Weight: Already a heavy platform at -+4700lbs, any add-on increases weight requiring more energy to roll.
5. Any suspension mod adding height. Due to high profile and relatively flat front, already pushing a lot of air (Resistance). Height of increased ground clearance increasing air running under the vehicle = increased resistance.
6. Fuel in terms of running regular or premium and summer/winter blend. For example, back here in the Northeast, Summer premium works best in my runner with better throttle response. Winter blend fuels negatively affect response and MPG.
7. Road Surface conditions: Affect tire contact and certain type of road surfaces create higher levels of friction=more energy to accelerate and maintain speed.
I like all aspects of my TRDP. No doubt all of us want 350RWHP and 400+ pound/feet of torque coupled to either a short throw 6-speed manual or 6/8 speed auto and getting 20+ mpg. Not on the 5th gen runners.......
Maybe we will see this in the 6th/7th Gen runners. Time will tell