Originally Posted by Nealrap
I am only getting 16mpg on my 2014.5 pretty empty.
How do you get better mileage? I drive about 65-70mph
Fuel economy is actually quite variable, and depends on a lot of different factors. Altitude. Temperature. Windspeed and direction. Driving speed. Regular diesel vs B5 diesel. How long you sit still with the engine running at idle. How hard you accelerate.
The sweet spot for fuel economy seems to be about 45mph. Faster or slower I'll get less. I drove across the Lake Pontchartrain Causeway, 24 miles, at 45mph due to fog restrictions, and topped out at 22.1mpg just as I exited the bridge, my best fuel economy ever in my Interstate. The listing dropped again as soon as I hit my first red light after the bridge, though.
On one trip, coming back to New Orleans from Lake Dardanelle in Arkansas, my average for the trip was a mere 14.7mpg. I was understandably concerned about that, but on the very next trip, I averaged 18.2 mpg. It dawned on me later that coming back from Lake Dardanelle, I was pushing the limit the whole 500 miles because I was in a hurry to get home in time to report for work, and driving much more aggressively than normal.
If I toggle the screen displays to the "Since Reset" readings, my average over 10,000 miles since I did my last reset was 17.7mpg. Which is a respectable number for a 5½-tonGVWR van conversion.
What I took away from my experiences is, if you drive like a feeble old granny who's afraid of traffic, you'll get great fuel economy. If you drive like NASCAR, you'll get crappy fuel economy. If you drive anywhere in between, you'll do well enough, but not anything to brag about. It still beats the 10~12mpg that you'd get from a gasoline-powered van conversion!