Product review (5 stars): Parts replaced under extended factory warranty
It looks like this is a poorly designed part, probably considered a factory defect.  I called the Kitchenaid help line (800-253-1301), explained my problem, gave them my Model number (KUDS30IXWH1) and Serial Number.  I was told that there is an extended 5 year warranty on these parts.  They asked if the roller wheels on my machine were gray or white.  (Mine are white).  They are sending me replacement side brackets at no charge.  They should be here in 7 to 10 days.  The lady was very nice.  I appreciated her professionalism.  I had always heard good things about the Kitchenaid brand, and would have expected no less.