So i just bought a 2wd 2008 silverado with the 5.3. The truck is bone stock except for fender flares and a soft roll up tonneau cover. I always put in 89 octane at the pump and haven't used any fuel cleaners yet. I have the stock tires on it to. The problem is i am getting between 11.9 and 13.5 mpg in the city. Im wondering what you guys are getting with your silverados and how to improve gas mileage. My truck does have the AFM but it doesn't kick on in the city anyway. What are your suggestions on fuel cleaners? I was thinking about doing a high flow filter soon but i cant afford any high flow exausts for a while.
Its also spring here and about 25 degrees so i dont know if that would affect my MPG