I cannot believe the mileage some of you are getting. I have a 2017 crew cab, 5.3, 4x4 with max trailering package and 3:73 gears. I was struggling to get 14-15 mpg on stock size tires. I just put LT275/70/R18’s on my truck, and I’m getting closer to 12-13 mpg. I’m driving like a grandpa! This mileage included was before I installed my new tires. This is one thirsty truck.