Can You Clean Headlights with WD-40?

Originally posted on Men's Journal | By Emily Fazio | Last updated Dec 19, 2024 10:00 AM ET

Foggy headlights are a common problem caused by oxidation, road grime, and UV exposure. Simply put, it happens, and it'll continue to happen. If you’re looking for a fast way to restore the shine to your headlight lenses, WD-40 is often touted as the perfect solution. While it can improve the appearance of cloudy headlights, it’s not necessarily the most effective solution or lasting fix.

How Does WD-40 Work on Headlights?

WD-40 Multi-Use Product is a water-displacing spray with lubricating and cleaning properties. When applied to clouded, foggy headlights, it adds a temporary layer of oil that makes the hazy headlights look clear and shiny. This is because the oil fills in microscopic scratches and masks the dullness caused by oxidation of headlights.

Want to try it? Here’s how:

Clean your dirty headlights with soapy water. It's important to remove dirt and debris.
Spray a small amount of WD-40 directly onto the headlight lens or (preferably) onto a clean lint-free cloth.
Gently rub the entire headlight in circular motions until the headlight haze is gone.
Wipe away the residue leftover with a clean cloth and polish headlights.

Looks great, right? While the results can be impressive, the effect doesn't last for an extended period. The oil eventually wears off, leaving the headlights with the same foggy residue as before.

Is WD-40 a Permanent Solution?

WD-40 Multi-Use Product is more of a temporary fix than a permanent solution for foggy headlights. Its main benefit is that it’s a quick, cheap alternative and widely available. But if you’re looking for long-term results, it falls short. Here’s why:

Doesn’t Remove Oxidation: WD-40 doesn’t actually remove the underlying oxidation; it only masks it. For a lasting fix, you’ll need to physically remove the oxidized layer using a more abrasive cleaners or a more aggressive method, like wet sanding or polishing.
No UV Coating: One of the biggest causes of foggy headlights is UV damage, and WD-40 doesn’t offer a protective coating against it. Without a UV-blocking sealant, your headlight lensing will continue to degrade over time.
Can Attract Dirt: The oily residue left behind by WD-40 can attract dust and dirt, potentially making your headlights look worse in the long run.

No WD-40? Try This Instead

Toothpaste: Mixing brands of toothpaste that are mildly abrasive with baking soda can scrub away oxidation with a little elbow grease. Results may vary.
Headlight Restoration Kits: These kits include sandpaper or abrasive sheets, polishing compounds, and UV sealants for professional-grade results.
Baking Soda and Vinegar: This DIY mix creates a gentle scrub to tackle grime and get your headlights clean of oxidation although results are mixed.
Sanding and Polishing: For heavily fogged headlights, a process of sanding with fine-grit emery paper followed by polishing with a microfiber cloth can restore clarity and shine.
Professional Restoration: Probably the best solution for reclaiming the original brilliance of your plastic headlights is to take it to professional detail shop and let them do the headlight restoration.

FAQ

Can WD-40 damage my headlights?

No, WD-40 won’t damage your headlights if used sparingly but it also won't give you spotless, crystal-clear headlights. Its oily residue can attract dust and dirt if not properly wiped away. Overusing it without cleaning excess product off the entire surface can also leave a greasy film that may reduce visibility.

How long does the WD-40 effect last on headlights?

The clarity provided by defogging headlights with WD-40 typically lasts a few days to a couple of weeks, depending on your driving conditions. Rain, dust, and regular car washes can wear away the oil, requiring reapplication for the same effect.

This article first appeared on Men's Journal and was syndicated with permission.

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