Ram 2500 5.7 hemi mpg.....a bit disappointed

I see pretty much the same results with my 5.7l. A little better in the warmer months when the winter tires come off and use of winter gas ceases, plus less warm up time and idling. Best I can get is 18mpg but that's rare, and much slower than 75mph.

The 6.4 supposedly gets better mileage since it has cylinder deactivation technology which the 5.7 in the 2500 does not get, even though it is available with the same engine in the 1500. I guess the 2500 is just too heavy for it to activate.