50% seems pretty low. I'm surprised
I bought an 07 Chevy van with a duramax in Tulsa. Had 140k miles, loaded, fully equipped with HVAC related racks and stuff. Bought it for 14k. An 07 gas van was going for 12-15k. I get 16-18 miles per gallon around town and can tow a trailer like a mofo.
Curious, What kinda mileage you getting with your duramax on long hauls?
20+. The new truck has about 6k miles and I got 22 on a trip to Greeley Saturday.
My brand new work van f250 at my previous employer got 5-7 mpg. F that.