There's also the Mazda Van, which looks like a copy of the Ford EconoVan (or more likely the other way around).
You could do the usual mods :
- (partially) Block the grille , starting with the upper opening, and keep a close eye on coolant temperatures. You can have more blockage in winter, less in summer depending on ambient temps.
- Fit an air dam under the nose. Extend it as low as the lowest part protrudes underneath the chassis.
- Fit a belly pan so it gains a smooth underside.
- Ditch all excess weight.
- If you're really committed : fit a boat tail to the big squarish van tail.
- Change your driving style to be more economical - or adopt an economical driving style right away.
Read through the
100+ Hypermiling / ecodriving tips & tactics for better mpg - EcoModder.com and try to apply as many as you see fit / deem safe / are practical for you.
Given the high mileage, I'd look into the diesels for this kind of vehicle, and see wether they'll take B100 biodiesel. These are still simple, sturdy diesels.