Thanks for everyone's help trying to diagnose this noise. I've been
underneath twice and everything is tight down there, nothing looks out of
the ordinary. Neither axel moves at all. I tried the circle parking lot
routine but it did not make any noise going in circles, it did however make
it slightly in 2nd gear going straight. I guess it was easier to hear it at
low speeds in the quiet parking lot. I drove it against a long brick wall
and heard nothing. It also did not make the noise the rest of the day.  I
think this is going to be a job for "the man" I'll drop it off at the
mechanics this week.

Anyway, last months problem was solved with a new O2 sensor this week so
thanks everyone for that. The new coolant hose and fan relay are in too.

My vans not happy unless something is broken. ;)

Bryan