I didn't take the time to do the conversions, but I get between 13-15mpg in town and 22-25.5 on the hwy. From what I have seen, the 4.4i gets similar in the city, but a little less on hwy around 18-20. My hwy speed is usually around 70mph (120km). If it is milage that you want, the 3.0d is what you should look at if available. I love my X5 3.0i. You can get almost everything on it as you can on the 4.4i except the comfort seats and a few other things. The savings of $10,000 was worth it.