Rick's Free Auto Repair Advice

Can you clear up cloudy headlights with WD-40?

Can you really clear up cloudy headlights with WD-40?

You can clear up cloudy headlights temporarily with WD-40, but it won’t last for long. You’ll find lots of other home-remedies for cleaning cloudy headlights. None of them work for very long either.

How does WD-40 clean headlights?

The main ingredient in WD-40 is solvent naphtha. It’s a cleaning solvent used in laundry soaps and cleaning fluids. It’s actually the main ingredient in paint thinner and mineral spirits. In addition to naphtha, WD-40 also contains a light oil, a wetting agent and some fragrance.

It’s the naphtha that cleans dirt off your headlight lens, but any car wash soap does that. So why does your headlight look shiny after you apply WD-40? It’s the oil; you just put a light film of oil onto your cloudy headlight. Will that shine last? Nope. Did you actually solve the problem of cloudy headlights? Nope. Does WD-40 even list their product as a recommended way to permanently fix cloudy headlights? Nope.

Why headlights get cloudy

Modern headlights are made from polycarbonate. Polycarbonate is an easily molded thermoplastic polymer that offers heat resistance and optical clarity. If fact, polycarbonate is one of the plastics used for eyeglass lenses. In addition to its heat resistance, polycarbonate is 250 times stronger than glass and is highly impact resistant; an important feature for headlight lenses.

But polycarbonate headlights scratch easily, just like your eyeglass lenses

Since headlights have to exist in a rough environment where they get sandblasted with rocks and dirt, carmakers apply a scratch resistant clear coating over the entire polycarbonate lens. It’s the clear coat that degrades from sandblasting and the sun’s UV exposure. And it’s the clear coat that turns cloudy.

• WD-40 can’t possibly restore the damaged clear coat. It just coats the entire surface with oil that makes it look shiny.

• Toothpaste polishing can’t possibly restore your headlights because it doesn’t remove and restore the clear coat.

The only way to clean cloudy headlights and restore them is by removing the clear coat, polishing the polycarbonate lens and applying new clear coat.

Which headlight restoration kit to buy

Many companies make headlight restoration kits. Mothers Headlight restoration kit, for example includes different sanding discs for your drill and plastic polishing compound. But it doesn’t come with any clear coat.

The Sylvania headlight restoration kit includes sylvania headlight restoration kitcleaner, sandpaper, plastic polish and clear coat. I’ve used it and it not only works, but it lasts a long time.

3M also makes headlight restoration kits as well as packets of clear coat.

3m and meguiars headlight restoration kit
3m headlight clear coat

©, 2023 Rick Muscoplat

Posted on by Rick Muscoplat

Custom Wordpress Website created by Wizzy Wig Web Design, Minneapolis MN