OK I have just read another post that someone on this forum is getting 20+mpg in their 5.9 Cummins. Can we all be truthful with each other? Please. I CALCULATED mine at 14.5mpg (the lie-o-meter showed 18-19ave) the other week. I am severely disappointed but with 10 years of owning the truck I have never seen better than 17. I have a freshly rebuilt trans and Tcase, 25K on injectors, bigger intercooler, cold air intake and many other new parts, brakes, U joints, and other parts that reduce friction. I just think people speak out of their :bart: or are :beer: when it comes to mpg discussions. If I am wrong please correct me and I will make adjustments to my truck to get the 20+mpg. Oh and I drive it very conservatively.