^^^Bingo, they are anodized. Polishing won't bring back the original luster. I would say if it bothers you have them powdercoated. Maybe $150?

I actually like my racks and don't plan to delete them, but I may powdercoat them someday, I took off some oxidation with a metal polish but it didn't bring back the color.

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2018 Ram 2500 6.7L Cummins 68RFE
19k miles -Bright White/Black - Big Horn Sport - Crew Cab Short Bed
2013 X5 35D (CEO's) - Born on 5/17/2013 -
82k miles - Alpine White/Cinnamon Brown/Premium Pkg, Sport Activity/Premium Pkg and Sound/20" Style 214/Running Boards