I have a97 k1500 z71 5.7 and i get 13 city and 16 highway, and that is after doing dual exhaust, k&n intake, throttle body spacer, tornado fuel saver. I also have bigger wider tires which doesn't exacty help the mileage. I have had to replace the fuel pump, I now have 147,000 miles on it. Over all a awesome truck, highly reccomended
