In Germany we're easily cached by police when we're closing up too
much to the car ahead. Trucks are doing 55 mph here, a bit slow for
a Vanagon. Keeping a distance of 100 feet give a bit fuel saving, but
uncomfort driving in turbulenced air. I did a high speed test last week,
110 mph speedo reading. I have no idea about the mpg, but a waste of
fuel I think.

Helmut
'80 Camper