ECO MPGs...not what you think
 

To the Guys that have been getting lousy MPGs on 2013 ECOs (like Me)
I decided to run the **** out of it for a tank full as I was getting 13-14 MPG anyway how much worse could it get? Dealer could find nothing wrong with it and no CEL light!
SO I drove the truck like a patrol car as I was either on the fuel or on the brakes. My Trans groaned the engin made strange noises and brakes stunk at times, but at the end of that tank of fuel I was showing 14.8 MPG? Also my brakes felt better,trans shifted better and improved power. The truck would now hold 6th gear going up the Cajon pass at any speed.
I just ran another tank threw driving my normal way (old man egg under foot feed style) and averaged 16.4 driving same roads and routs as I always have when I was averaging 13-14 tops. Could it be that at 6000 miles it just wasnt broke in yet?

Could be break in and a number of other factors. If the weather is getting warmer around you? that helps fuel economy. Have you checked you tire pressure lately? Driving habits and weather conditions really effect the Eco. If you keep your speed under 65mph on the expressway and try staying out of the accelerator these trucks can get decent miliage. I've seen 23.5 mpg on the highway last week doing 65mph.

Mine improved from just my first tank of gas to my second. I'm getting 20mpg highway and ~17 mixed. My first tank averaged 15.5 so it's getting better. I'm also driving pretty conservatively. I'm setting cruise to 70-75 on the highway and taking it easy off the lights. Right now I'm at 17.6 avg mpg.

I didn't expect much better than that. I think that we're seeing numbers all over the place due to weather/conditions & how people are driving. I don't care how fuel efficient a vehicle is, if your driving it like its a rental your going to get poor gas Milage. A prime example are patrol cars. The 6cyl chargers don't do much better than the 8's because they are all driven aggressively.