I believe this to be a minor issue but nonetheless a defective part by Ford especially when six are removed during 1 visit at the dealers. I have contacted dealer and Ford customer service to be told this is a wear issue and not covered by any warranty including my Ford extended warranty. The part itself is a minor issue but the refusal of the manufacturer (Ford) to admit any poor design issues on this is rather astonishing and potential Ford customers should be aware of this issue.