The OP will have to clarify what he meant himself, but mileage has both a specific (miles) and general (distance) connotation. While there is technically a word kilometrage, I've never used it. In terms of fuel consumption, my X3 gets good mileage, which I quantify in litres/100 km.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue