We experienced cupping on the driver's side front in the midst of a trip to Canada.  I could hear the whopping sound while driving and see the wear pattern, so rotated the tires on that side. Still don't know what would suddenly have made that go out of adjustment.  Got home and fashioned a 14MM tool so I could adjust the camber on that wheel and it worked.  I tipped the top of the tire further outboard and guessed at the setting.  No unusual wear on that tire so I'm happy with my calibrated eyeball.
Stephen 

     On Monday, June 8, 2015 9:25 PM, Eric Caron <ecaron1@COMCAST.NET> wrote:
   

 Hi folks,

        Before leaving for Bus fusion I noticed that my front passenger tire is cupping on the outside edge.  all other tires are smooth.  tires have only about 3,000 miles on them.  I check pressure regularly and keep them all at 48 PSI. My van sticker says 48 rear and 39 front.

tires are 1 year old General Ultimax. 

Van was aligned 2 years and less then 6,000 miles ago and still drives straight down the road.
 
it seems strange that only one tire and only one side of the tire is cupping. It is mild at this point.  i can feel it but people can’t see it and often can’t see it until I have them move their hand over the tire.

        I have some recommendations as to what to try but I wanted to ask the list for ideas before I start purchasing things.

bus fusion by the way was amazing with over 200 buses and so many great people. It was a long drive from VT to Almonte Ontario but  now I have another reason to try to keep this bus running great.

Eric Caron 
85 GL auto Westfalia