We might have this one figured out after all. If we can agree that the
front of the vc spins in relation to the speed of the front wheels, then
with the center drive shaft removed the rear of the vc has no movement.
This should cause the vc to lock up and spin "unloaded in the breeze." A
test for this theory is to view the rear VC plate without the DS while the
vehicle is moving. Either hang on under the van or strap on a camcorder :-)

I don't think that a locked up vc unloaded would harm the mechanicals in
the vc. Without a load it is just spinning. The fluid is another question,
I disagree that it will keep heating up and up until it burns up. It should
heat up until it locks and will stay that way until it comes to rest. Once
it locks the friction stops so does the heat.

Just some ideas...  

Erik O
87' Syncro Westy Camper