Olden, I am in the same boat as you. I just purchased a 2004 Silverado, D/A, crew cab, 4x4, long box and even though I have put few miles on it, I am getting nowhere near the mpg that everyone else has been reporting. So far I have been getting about 13-14mpg totally unloaded highway miles at 75mph. As I have a broken leg right now I have not been able to investigate further(air filter, fuel filter, etc.) What gives?
2004 Silverado 2500HD D/A
Crew cab
4x4
Long bed
Red(of course)
Uniroyal Liberator A/T 285/75/16's
Bilsteins
Edge Juice w/Attitude
2003 CRF450-mine
2004 CRF150-wife
2003 XR70-daughter
2001 XR50-son
Yeah, we like the Hondas