I just took my MKC to the dealer. They said Lincoln issued a notice that water stains from rain and car washes can appear on the roof rails and to try what member 2015 MSM mentioned earlier in the post. My dealer tried that on another Lincoln MKC and it didn't work. Dealer is ordering new roof rails and is covered by the warranty. Dealer informed me the roof rails had a coating that was not up to par and Lincoln will replace them. Thanks for everyone's help. Everyone needs to check their roof railings