Just returned from an 2,280km round trip pulling a caravan. I'd hesitate a guess that somewhat over 99% of the trip was done on motorways (French) with Cruise Control used almost non-stop other than at Toll booths etc but even here, having a t-card meant we were sailing through at close to 30kmh. The outward journey of 1,140km was done during the time of the recent French strikes meaning that I couldn't be 100% sure that fuel (Diesel) was always going to be available and as a consequence topped up the tank on more occasions than was absolutely necessary just to be sure. Using the brim-to-brim method it works out that the fuel consumption works out at 10.6 litres/100km which considering that I had 1200kg of Caravan in tow I am more than pleased with. Non towing figures aren't really that much less.
Only hick-up and I mention it only in passing and without the intention of inviting further discussion, was that the tyre pressure warning light illuminated approx 200km into the journey. Upon checking the tyre pressures this turned out to be a false alarm with the light going out after an engine restart. Darn annoying all the same but I'm thankful that at least the dreaded diluted oil light didn't illuminated. Also never once noticed (smell) the DPF regeneration which must have happened several times which is probably down to the driving at motorway speeds etc.