Sad to hear. Like Textured Black Plastic Trim, once any form of anodized aluminum is stained, there's not much you can do to fix it.
Anodizing is an electrochemical process that converts the outer surface of the aluminum into aluminum oxide. This protective layer grows both into and outward...
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Even if you are only using a spray-on sealant or coating, there's still a possibility for staining or altering the appearance of trim. I found these pictures on a Facebook Detailing Group. I apologize to the owner, I should have reached out to get permission to use the pictures...
Considering all aspects you just described, here's what I would suggest.
After washing and drying the truck, tape-off any trim you don't want to accidently stain. The best way to avoid stained textured black plastic trim is to avoid getting anything on it in the first place. See my story...
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🏁 FINAL RESULTS—1969 Plymouth Roadrunner! 🏁
Six steps. A whole lot of focused work. And THIS is the result! 😎✨
From orange peel and distorted reflections to deep purple gloss, crisp reflections, and ceramic protection—while preserving and protecting the matte black paint on the hood...