I have a 2500 low-roof with the V6. The computer is not good to go by, even when resetting at each fill up. Calcs of miles divided by gallons is the best. Mine is new, 1000 miles, 40/60 highway and city, gross weight with tools and equipment is 7900 lbs as it stands daily....I am seeing 16 mpg right now. I am hoping it improves with more miles...can't really go by readings at a 1000 miles. I am curious what the high roof does to mileage and handling with the V6....we are looking to replace Ford E-250's and E-350's as they die off.....NV is the only good replacement, prior to Ford moving to the European Van after next year, to replace the E-series service vans. We have had Chevy's they just don't hold up.....Sprinters don't have a good reputation around here and are more $$. Eager to see how others experiences with the NV are coming along.