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01 2020 Ram 1500 Rebel Sunset 1

Why Custom Headlights Get Moisture In Them (Spoiler – They Aren’t Defective)

Which Are Ideal For Rain & Snow?

When you’ve got some awesome looking custom headlights, the last thing you want to see when you walk to the front end of your vehicle to check them out is moisture inside the lens. It might look like a foggy cloud from the sky was sucked into your headlights, reverse genie-in-a-bottle style. That thing is just hanging around, causing moisture to slowly drip down the inside of your headlight lens like some type of agonizing torture.

But fear not! This moisture doesn’t mean your headlights are defective or broken. It also doesn’t mean you need to go out and buy a whole new pair of headlights like some dealers would have you believe.

How Does Moisture Get Into Headlights?

So wanna know how that moisture gets inside your headlights in the first place? Hope you paid attention in science class. It’s called condensation.

Condensation happens when the outside of the lens is cooler than inside the lens. When you drive around with the lights on for a few hours, the bulbs warm the air inside the headlight lens. The same thing could happen when the headlights sit out in the sun all day.

So now the air inside the headlights is warm. Turn the lights off or pull your vehicle into the shade and suddenly the air inside is much warmer than the outside air. So that warm air hangs around for a while with the cool air just watching it from outside the headlight. The cool air wants inside. It wants inside so badly that it begins to sneak into the tiny vents that are found on most headlights at the top and bottom of the headlight. When that cool air meets head-on with the warm, condensation is formed. That happens on the warm side of the lens, so you’ve got a little layer of moisture on the inside of the headlight lens.

Turn the lights back on, crank up the temperature outside the headlights (or pull it back into the sun) and that moisture will eventually evaporate.

Brand New Headlights

Brand new headlights may have condensation built up inside them because they were shipped from a very dry climate to a not so dry climate. The not so dry climate causes the condensation to build up in the headlights. Even brand new cars on the lot have this problem. The good thing is, it usually clears up in a few days.

Another Reason

There is another reason your headlights could be filled with condensation. The bulb socket boots may not be seated properly. When the headlights are on and hot, that heat will pull moisture in through those tiny spaces where the boot isn’t sealed right. There’s your condensation. To fix this problem, just remove the bulb and the seat and then install it correctly. If the boots are old they could be just worn out and need to be replaced.

Vent Tubes Can Help

Almost every headlight has a vent tube. This does not let water into your headlight. This tube is actually there to allow condensation to escape. Don’t try to plug or block the vent tube or you’ll end up worse off than you are with a little condensation in your headlights.

What If There’s Water Inside The Headlights

If you’re seeing a lot of water actually sloshing around inside your headlights it means the seal around your bulbs or headlight isn’t working properly. There could be rain water dripping into your headlights if that seal is busted or not seated properly. You’ll have to remove the bulbs and/or headlight and check the seal around them. Sometimes, when replacing your headlights with new ones, those seals fall off or just don’t seal back like they should. Get some new ones and your headlights will stop taking on water like Gilligan’s boat.

If you’re still finding standing water inside your headlights, you’ve got a crack or a hole in your headlight. Find it and you’ll find the problem. Even a small crack can let water in over time, so in this case you’ve got to get them fixed or replaced to fix the problem.

If you need any help with your soggy headlights, give 4 Wheel Parts a call and we’ll help you out. With more than two decades of custom truck experience behind the counter, we can give you good advice that you can rely on. Call us today.