> But who makes them FOR VW??  I bet you'd find that it's either
> Knecht/Mahle or Mann.

At present, my guess would be Mann, since the VW ones currently sold at U.S.
dealers are made in Germany, as is Mann, whereas the Mahles are made in
Austria.  However, I believe that both companies have supplied Volkswagen at
one time or another. I personally have not found any reason to prefer either
over the other; both meet Volkswagen specs.

- Ron Salmon
  The Bus Depot, Inc.
  http://www.busdepot.com