Few weekends back drove Brisbane - Sydney - Brisbane on the Coast road both ways.
Truck was empty except the sea anchor and I, a couple of overnight bags and a 40KG lump of ally in the back. Pretty much drove down, across Sydney and then back so figured I should get about as good a fuel figures as I was ever going to.
On the freeways I sat on 100kms/hr confirmed by the GPS.
Started with full tanks, drove 2,039kms and ended with fuel tanks having used 239L which by my maths works out at 11.72 l/100kms. Truck had done 57,500kms at end of trip.

