I drive a BMW 320d, production July 2008, with automatic gear shifting. Using the automatic speed control at different speeds on a relatively empty German highway I discovered the following fuel consumption pattern:
120 km/h: 5.2 litres/100km
140 km/h: 6.5 litres/100km
160 km/h: 7.6 litres/100km
180 km/h: 9.0 litres/100km
200 km/h: 10 litres/100km
Quite interesting...
