biggest size van with lowest cost to drive with a OE gas engine and auto trans?
"its the most aro" thus an advantage in that respect.
the 90s/2000s dodge 1 ton 15 passenger with OHV 5.2L 318-V8
they can pull 20+ mpg on the open road, oddly good for there size.
The V8-318 dates to the mid-late 1960's. Chrysler never had the money of Ford or GM, thus car engines had to be made reliable for
commercial truck work. And this motor fits the bill. Super long-lived. Not celebrated for HP, but keeps running with a minor overhaul when the Ford and GM light truck V8s are on their last miles.
While I haven't known anyone to get 20-mpg, the bulletproof motor and equally bulletproof A727 transmission would make any and all other work easier to accomplish.
Another forum for the OP to read is
ExPo: Adventure and Overland Travel Enthusiasts
Don't forget that several tons of vehicle to sleep inside and carry motorcycles, etc, might be better with another vehicle (Jeep JK) that can easily get above 20-mpg (as a friend of mine has done with his 2007, man trans and low options).
Pulling a trailer optimized for layover bike storage and with a FLIP Pac tent might be a better option for a budget.
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