Dodge achieves that mileage with a short box 2wd work truck, no options. That way the truck is as light as possible. The truck also has a new 8 speed automatic transmission which helps a lot.
Remember this line... "EPA estimated mileage" This is very important. Automotive manufacturers cannot technically self certify their mileage, but can use their own estimates by running the EPA test. The EPA has went back and make OEMs correct their OPTIMISTIC mileage predictions. Hyundia/Kia are in a class action lawsuit right now because of their erronous claims.
To your question, I bet that Ram truck is pretty close. Another thing to remember, most people dont drive like the EPA test so dont expect 25mpg unless you baby it.
My truck stickers 21mpg on the highway. I can get 19+ with it. This is driving very easy at 65mph. crew cab 4x4, 5.3 Chevy. It use to get almost 21mpg before some dummy put a lift kit and bigger tires on it. I look at the dummy every morning in the mirror.
My two cents.