Yep, sounds like busted belts in at least one of the front tires, usually damage from hitting a big
pothole or a curb.  I had this in one tire and when going very slow the steering wheel would jump
every time that spot hit the ground.  Cheaper passenger-rated tires are damaged easily like this.
Mount the spare on the front passenger side and see if the problem disappears.
-Hans

----- Original Message -----
From: "Leo Lee" <leo0365@SBCGLOBAL.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, April 08, 2005 12:39 AM
Subject: Steering wheel or brake pulsing???

> The problem began while I got out of the freeway, slow down on the local and noticed that the
> steering wheel pulse/shake to left side of the vanagon. The pulse rhythm appears to follow the
> turning of the wheel, the faster the wheel turns, the faster the steering wheel shake. I jack up
> the front end, spining the front wheels, the driver side appeared to drag at some point in every
> turn. I shake the wheel, there appears to be a little loose. I then took off the wheel and
> tighthen the lock nut one eight of a turn, put the wheel back and test drove. The problem got
> worse. I check the history of the van, the brake disc was resurfaced once 50,000 ago, the mileage
> of the van is about 120,000, I thaught I had a warped brake disc, and it is probably about time to
> replace the brake disc anywhere. After replacing the brake disc, repack wheel bearings and the new
> pads, to my surprise, the problem still exist. I checked the front end carefully, I found two
> problems. 1. the rubber boot of the
> lower ball joint was broken, and there was a very small play when I pushed the wheel upward. I
> think this problem probably not the cause of the steering wheel shaking. 2. I found a small
> section on the front tire on the passenger side cave in a little in the middle, and become uneven.
> I have never seen a deformed tire before, not sure this will cause the van to shake. I let some
> air out of the tire (reduce about 7 psi) and test drive again. I did not feel any change at all. I
> am not sure what else to look for. I would appreciate any suggestion to the problems before I
> spend another $200 to replace the front tires.
>
> Leo, 1991 multivan 120,000 miles
>