My BIL had a Laredo bumper pull that turned from dark brown to completely white from oxidation. We tried everything from waxes to de-oxidizers with/without buffers. finally found Poli Glow (
https://www.poliglow.ca/) which worked. I ended up doing the front of my Redwood with it 3 years ago as well due to fading. I need to do it again, but it works. Quite a bit of work-but worth it. Follow directions to a "T" though.
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