I've had this truck for close over two years now and have done a lot of work to it, new exhaust from turbo back (3"), Tymar intake with high flow Donaldson element, new tires, stock burn TS performance chip and a bunch of other stuff that probably never affects mileage. I log my fillups every time so I can monitor mpg. Most of my driving is in the city where I get 15-16 but I took it on a little drive and got 17.99 mpg. I fill up my tanks until I cannot get any more into the filler neck when I do mileage checks so I know my numbers are accurate. I am pleased with the mileage.