I have a 2017 2500 SL cargo with the V6 engine. I use it more as an adventure van than as a cargo van, so I don't normally put substantial weight in the cargo area of the van. I also happen to have a lead foot. I normally have cruise control set to 90 mph when I am on a road trip. I average 13.7mpg to 14.9mpg depending on outside temperature and if I am climbing hills. When I bought the Nissan, I bought the V6 thinking that I was going to get awesome mileage. The trueth is that the V6 and the V8 get similar mileage. What I did not appreciate when I made my purchase is that I would be using the van to tow my ATVs around the country, If I am going to have to live with 14mpg, the additional torque of the V8 would have been helpful. I hope this helps.
