Yes, the Astro does have an electrical setup that will kill power to the fuel pump, if the oil pressure gets low enough. I'd heard something like this before, so I went hunting, online. Here's more info: http://www.10w30.com/thread-3934.html

My dad had a pair of those vans for his business, when I was young. They weren't my favorite thing, back then, but they were pretty [email]d@mn[/email] quick and hauled a lot of equipment, and 18 mpg sounds about right. I'd thought about putting one of those in my old Montero or a friend's Jeep for a while. I think it would be a good swap, both for power and fuel efficiency.