Diagnosing from this far away is prolly impossible...

However, first things first...

Before driving anywhere else, check to see what may be "different" or
"low"...Tranny, steering, brake, coolant...for the life of the
components, and safety!!!

I am probably overstating the obvious, and it may not help you in
tracking it at all...like mentioned before, it doesn't take much oil
to make a HUGE mess!!!

I had a Chevy 350 in a mini motorhome that had the PCV set up
incorrectly and it blew oil everywhere...what a simple fix...looking
at what should be routed where...but at the same time, it didn't
appear to be losing that much oil....

Was this van sitting for a while? Do you have reason to believe that
it would be losing oil from major seals???

If the oil was just changed, I would check the oil drain and
filter...Kind of stinks that its 100 miles away from ya...

Good luck!

Dave
85 GL "Baby Bus"
85 "No Name"