Other luxury cars/SUVs require premium gas. Diesel could be same or even cheaper than regular gas and with immense torque and a somewhat light foot I get almost 25Mpg
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2009 Mercedes-Benz M-Class Gas Mileage (MPG)
Unlike other fuel economy surveys, TrueDelta's Real-World Gas Mileage Survey includes questions about how and
where a car was driven. So you can get an idea of the Mercedes-Benz M-Class's
real-world MPG based on how and where you drive a car.
What Our Members Are Saying about the Real Gas Mileage of the 2009 Mercedes-Benz M-Class
7-speed shiftable automatic AWD