I bought this thing one year ago with 100k on it and it and it was getting 15mpg. Now at 140k the mpg is at 13, it has been slowly getting worse. This is a big dissapointment considering that my old 85 chev with 150k on the 6.5T gets 20mpg consistantly. Whats wrong with this thing? It runs fine and has tons of power and no mods that i know of besides cat delete.