Originally Posted by worthywads
I wonder what they have improved over the years, the highway mpg stays at 25 but the city is up from 18 on my 2005 to 21 on the 2013? In 2007 city went to 20, then 21 in 2011. A few years along the way the highway has gone to 26 and then back again?
Lower fuel consumption at idle? Lower viscosity oil? Different low rpm tuning? EPA gamesmanship?
They probably took notice of the numbers you were posting (along with others in this thread) and figured, "What the heck!!"
I've noticed across all makers that run an engine configuration for extended periods (several years) that they generally can tweak it for better MPGs and often times an HP here or there. Definitely gamesmanship in play here as you can see by the rankings, most trucks are within a digit or two so to claim top spot, not much needs to be done. Subtle refinements in the truck to smooth the lines, oil, different software for the idle/transmission shift points. I suppose the game can be played a number of ways.