Some of my real world numbers. Taken from the odometer and fuel pump readings. My speedo is about 2 km/h out - reads 100 km/h at 98 km/h.
Average of the last two trips. Lightly laden up, heavily laden back. Sitting on the speed limit, cruise control when practical. Overtaking trucks with "enthusiasm..."
Melbourne to Hervey Bay via Newell, one stop for fuel - 8.4 l/100 km
Hervey Bay to Sydney, straight down the coast, Brisbane at morning peak hour, no stops, 11 hours roughly - 7.2 l/100 km
Sydney to Melbourne, Hume Highway, no stops, about 8 hours - 8.2 l/100 km
Cheers
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