In response to your self-tightening question. Could it be that the lug
"bolts" are tightened the opposite direction the wheel turns and over
time become tighter? This is what the previous owner told me, and I broke
a  socket wrench reaching the same conclusion. The fourway cheapo spanners
are BTW useless for taking off VW lug "bolts". I found slipping the hollow
end of the jack over the wrench gives more torque BTW.

It may also have to do with the greater surface area a lug bolt has (and
potential for rust etc) over a conventional nut. Maybe some engineer can
tell us the physics behind the different designs?
DC
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David Carment
School of International Affairs
Carleton University
Ottawa, Ontario
K1S 5B6
voice - (613) 788-2600-6662
fax - (613) 788-2889
Email address: dcarment@ccs.carleton.ca
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