Originally Posted by JAWS37
My 04 2500 CC diesel with a K&N filter gets 27.2 highway based on the overhead console. The key is to pretend there is an egg between your foot and the pedal. This was done driving around the beltway of DC. The truck has 150k miles and purrs like a kitten.
The overhead is notorious for being way off. The only way to get an accurate reading is to hand calculate it. My overhead told me I was getting 22.5mpg on my last trip, hand calculated it came out to 16.7mpg.
Same drive my overhead was reading 16.5mpg when hand calculated I was getting 14.5 (towing)...so there is a bit of variation.
While driving it easy on the highway will net more mpg, id be surprised if you actually get more then the low 20's on the highway.