Mercedes ML55 AMG : On a 271km flat out trip : 29.9litres per 100km.Top speed 242kph.
BMW X5 4.6iS : as above : 31.7litres per 100kms. Top speed 250kph.
Porsche Cayenne : as above : 48.1litres per 100kms. Top speed 280kph.
The Porsche has a 100l fuel tank and needed refueling every 200km's.
Overland 4WD achieved these figures in the NT.
Not bad for 4WD. !!!!