Need some details on your truck. What size of tires? Lift kit? City or highway driving. Lot of variables to go by to figure if your getting good fuel mileage. Wifes 06 in my sig gets 15 mpg hand calculated. But seeing winter is here it will drop.
16 seems right in line with what i would expect with your truck. Alot of guys prefer smarty for the older 3rd gen trucks. I'm going to get efi live after I get tranny built.