When I first got my truck, That is about the best I was getting too. But after about 3000 miles and a full synthetic oil change, it started climbing. There is another thread there that discussed it. I was happy when it cleared 26 mpg on the same run and when it passed 27 I was estatic. The truck is at about 7500 miles and had 2 full synthetic oil changes. I'm changing it every 3000 at this time. Wally full synthetic is about the same price as others conventional oil. Who would ever think that you could pass the factory highway estimates this much? I belive that the highway epa listing for the 4wd is 1 mpg less. I'm a conservative driver, Occupy the far right lane and run about 60-65mph with or without cruise control.
I run 100% Synthetic in all my vehicles and my motorcycles !
Even when I had on the SRA'S I got the same MPG.
And no difference with my Good Year AT/s , They are a 4 ply so not real heavy !
The NEXAN Dedicated snows were 10 ply and I did drop about 1 mpg with them !
But my Window Sticker MPG was rated at 23 MPG for my 4x4 Quad Cab so I am pretty close
But would LOVE to see 26 MPG lol
Iknow a truck will not get 40 mpg :O But I do want the best mpg my vehicles can get ! IMO by following your mpg you may see a issue starting when it drops a lot