My 3.3m high 7m long Iveco van has a 3 Litre 210 horsepower diesel with an 8 speed auto, with duals on the rear. I scrolled through the settings the other day. I have done just under 10,000km. My average fuel use has come up at 7.3L per 100.
A lot of my driving has been crossing the range from coast to tamworth to move all of my equipment and parts, some loads have been at full weight (8.5T) I am rather impressed at fuel use, it is not a slouch either.
this is better than my triton ute, the average on it is around 9.9L per 100. I often see 10-12 L per 100 on fuel use setting. In the morning going to work i have it as low as 7.6 some days, others high 11's. the triton doesn't have the lifetime average on screen.