I was lucky to get 14 mpg average city/hwy on my X. I have a 2 inch body and 3 inch suspension lift with 33's, ARB, winch, rear swing carrier and rock sliders. I added the snorkel with the drop-in K&N and now I get 16.5-17 mpg. Same route to work and same driving habits. I understand the physics that Kerensky mentioned, but some how my situation works.