Karl,
I think that the glitch in this theory is;
Where is the oil pick-up?
In the bottom or top of the engine?
So, regardless of where the oil is foaming, the oil will still be picked
up and delivered, unless of course there is an worn out pump, where it
can't be delivered at optimum pressure, or like you stated, the van was
going up-hill, and possibly starving the pump from the oil supply,
causing a temporary over heating situation.

I want to know what would happen, if in fact the same picture was being
painted as he was going up this hill, pulling this other van, with low
oil.
Would the van have gotten as hot?
Would it have gotten hotter?

Interesting--------

The reason I brought up the larger oil pans of a Mack, was it was
somebodies contention that the less oil you run the cooler the running
temperatures.
This is just not so.
Or did I mis-read this, and this phenomena only occurs in a Vanagon?

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Terry--
74 Campmobile- (Clementine)
85 GL- (Delilah)
86 BMW 325 ES- (Eva)