70 series TDV8 fuel consumption

G'day all

Have just returned from the Kimberley's 5 weeks of pleasure. 8,000 kms towing our Pioneer Camper trailer

Fuel consumption is around 6km / L at highway speed of around 100 - 105 kph (allowing for speedo error ex factory). Didint seem to improve much when slow 4x4 of road without camper...maybe a little less than 7)

Question to those with the same vehicle. How does that feul consumption compare...have any put a chip in? ( if so which one) or modified the exhaust? (if so what)

did anything positive happen that encourages me to do the same?

thanks all