We have a 3.5 litre petrol auto Monterey (Jackaroo with gay alloys), and drag a 1.25 tonne loaded CT.
We recently got 65mpg ( I need to reset the scangauge to metric) on a run of 6 kilometres, boy was I impressed, but that is only coming down the Toowoomba range towards Brisbane.
The rest of the time we average 15 to 16 l/100k travelling around 90kph on real roads, but that jumps to 18l/100k at 100kph.
Dirt roads are around 15l/100k at 80kph, probably due to corrugations and tyre slip, and roads around St George returns around 45 litres/100k, because the bumps are so bad, the revs increase significantly when all the wheels are off the ground.
The vehicle has a snorkel for improved breathing, and the exhaust restrictors are removed and a semi sports muffler installed for improved flatulence relief.
Head winds, hills etc obviously results in worse figures.
Cheers