I've notice some have
I've notice some have questioned the mileage while towing. My 2015 quad cab 4x4 ecodiesel still maintains an average of 19mpg highway with just over 7,000lbs in tow. It's been an amazing truck. No complaints. It tows with ease, steep grades really are no issue. I should also mention that I have modified the truck. It's had a leveling kit(lifted 2-1/2" in the front 1" in the rear) installed and is riding on 35x12.50 mud terrain tires, I was concerned that this alone would significantly decrease my mileage. Still averages 22 overall and 26 freeway and has had no effect on the power. Very very impressed.