When you ask about MPG, I think one should mention what year they have. I small underpowered truck running at 3000 RPMs will get less MPG than an engine that is bigger turning 1700 rpms. I have a 2006 for about a week and on the first couple tanks I have gotten around 20 mpgs.. I just read the article Xterra's DEATH VALLEY Initiation and he got 16 mpgs crawing around in 4 Hi and 4 LO all day.