General RPM range 2.3 engine

[rustygun]

Hi all. I have a 2008 fiat Ducato based motorhome 2.3 engine ( TD) 6 speed. Total weight 3020KG

I was fooling around with different speeds and RPM ranges with 5th and 6th gear to find the optimum mileage per liter. So far my best results seem to be in 5th gear at 2200 and 95kph

Anyone found something similar?

Regards: Rusty