Had a similar problem with my 89 Jetta. Turned out to be a bad wheel bearing.
The wobbly bearing was the culprit which caused the tire to overheat and
blow-up. The bearing would only howl at certain speeds. Best way to check if
it;s your tranny or not is by driving at speed (on a clear road). Then put
the transmission on neutral. If the noise goes away, then it has something to
do with your engine or trans. If the noise does not go away then it's
something at the wheel like wheel bearing or warped rotor etc.

This can happen to Vanagons as well <mandatory Vanagon content>

BenT
<A HREF="http://hometown.aol.com/bentbtstr8/myhomepage/index.html">Vanagon
Cafe</A>

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