Purchased Bosch evolution wipers because I was unhappy?

2025 KIA FORTE
3,500 MILES • AUTOMATIC
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ALYLAROSA485
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  • 174 POSTS
In June 2026 I purchased Bosch evolution wipers because I was unhappy with the oem that were already smearing after less than a year of having my 2025 kia k4. Any idea what this is on the outer plastic part of my blade? Just noticed it recently and it doest’t rinse off or come off when wiped with microfiber rag . It’s a whitish blue stuff
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Sep 17, 2026 at 5:03 AM
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STRAILER
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From the picture, this appears to be discoloration or oxidation of the outer wiper-blade spoiler rather than a substance stuck to the blade. UV exposure, heat, ozone, car-wash chemicals or other environmental contamination can cause black rubber/plastic components to develop a whitish or bluish haze.

Since you've already tried water and a microfiber cloth and it doesn't come off, I wouldn't use any strong solvents or petroleum-based cleaners on it because they could damage the spoiler or wiping rubber.

More importantly, inspect the actual rubber wiping edge. If the blade still wipes smoothly without streaking, chattering or leaving unwiped areas, the discoloration is probably cosmetic. If the rubber itself is becoming gray, cracked, hardened or distorted—or the blade has begun streaking—I would replace it.
Sep 17, 2026 at 11:49 AM
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