Tire going out of round is a problem more common than some would think. If slight balancing may take care of it. This is one reason tires rebalancing is often recommended as maintenance. This can also be a sign of a tire failing. A tire having tread does not mean it is usable. Tire problems do tend to occur during long trips as the heating effects do the damage. Have t hires checked and balanced. If fairly new you may be able to get a warranty adjustment. The failure term is known as "Ride Disturbance".  
Bad shocks will often cause scalloping, not out of round.  

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Matthew Christensen
Sent: Friday, March 05, 2010 8:00 PM
To: vanagon@GERRY.VANAGON.COM
Subject: bad shock?tire ovals

Hello List, I have a few questions that maybe someone can answer. I replaced my old shocks with bilsteens HD from ebay as my old shocks were bottoming out, as I drove my large father as a passenger in the front seat. I replaced the stock shocks and took a 3,000 mile drive to and around FLA,. When I was returning I noticed the faster I went the more vibration I would get at 65 MPH +. So I spent the finale 4 or 5 hours of the trip driving at 50 MPH, and it seemed to work. After I got home, I jacked up the front right  tire, spun it, and it was mildly ovaled. I replaced with the back rear tire and put my spare on the back. It  seemed to fix the problem, but it feels weird driving. Slight vibrations and pulls to the right. Thanks Matt NJ 

My quesitions are:Can or will a shock oval a tire? 

                         How can you tell if a shock is bad? 

                         Would alignment cause this problem? 

91 2.5 Vanaroo Westy-Baloo 

88 2.1 Vanagon Westy-Arlo 

87 GL Wolfsburg Weekender-Silver Bullet