As part of the front suspension see the discussion on those radius rod mounts. I'll bet they need to be done. These are an important part to maintain alignment as the suspension is working under changing loads. Both front tires wearing on the outside indicate a toe or major camber alignment issue. If the van likes to pull or tug to one side then you also have a castor issue. Back to the radius rod mounts.

Most low-medium speed oscillations are caused by tire or wheel issues. Of intermittent then shocks, dampers, worn parts can also be a problem. It is hard to really test the shocks in place. Pull them.  Non power steering vans are more sensitive. A tire place should be able to check the tires and wheels for run out or out of round. With the excessive outer wear most likely the belts are pulled adding to the ride disturbance.

Dennis,
And I still can't type on this Windows 8 Phone!
________________________________
From: Pat Patterson<mailto:SESRating@AOL.COM>
Sent: ‎1/‎22/‎2013 12:17 AM
To: vanagon@GERRY.VANAGON.COM<mailto:vanagon@GERRY.VANAGON.COM>
Subject: intermittent wobble at around 45 and above

Sometimes my van gets an oscillating wobble when at medium speeds.   When
passing or getting passed by a big truck is another time when it happens  but
not all the time.  I have had all the suspension parts renewed and the
wheels balanced and alignment checked.  My front tires have worn badly on  the
outside edges.  I am not in California anymore and have not been able  to
find the root of the problem.  My mechanic thinks my wheels may be out  of
true.  I plan on rotating my wheels front to rear to see if it changes
anything but do not believe that to be the problem.  I would really like to  get
this sorted out before I buy 5 new tires and if needed rims.

Any ideas?

Thanks,

Pat
in SC