I recently purchased 4 used rims and tires for my 940T from junk yard. The tires came from a car that had been sitting for some time. I cleaned the tires up and had them balanced and put them on my 940T. When I hit over 50 mph the front end started vibrating a little. I had the car looked at and was told that the belts on the tires had shifted? When I put my snow tires on the car's front end did not vibrate anymore.

Another mechanic told me that I could try rotating tires and driving for about 10,000 and sometimes this problem corrects itself. The tire threads are in great shape. I would hate to get rid of them.

Questions
1-Has anyone heard of this type of problem correcting itself?

2-When I store the wheels and tires during the winter...does it matter what position they are in. On the sides or upright?