They look funny, yet every new car tire has them. So why do tires have hairs?
This Is Why Tires Have Hairs, According to Car Experts
Updated on May 23, 2025
If you’ve ever looked closely at the tires on your car or touched the tires while wandering around an auto shop, you’ve probably seen those little hairs sticking out of the black rubber. And you wouldn’t be the first car owner to wonder, Why do tires have hairs? They’d be a strange add-on for aesthetics alone, but is there really a purpose to this weird car feature?
To get to the bottom of the tire-hair mystery, we asked car experts to explain what’s going on. Read on to find out all of the interesting facts the auto pros told us.
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What are those little hairs on tires?
Located on the vertical part of the tire, also known as the sidewall, those curious little rubber hairs are technically called vent spews—or more endearingly, tire whiskers. According to Will Robbins, executive director of strategic and product portfolio planning for Bridgestone Americas, these vent spews are a result of the tire manufacturing process and happen as the tread pattern mold is pressed into a new tire.
In other words, those tiny whiskers aren’t for function or flair. They’re just a quirky byproduct of making sure your tires come out cleanly from the mold.
Curiously, there’s no set number of hairs each tire will have. The exact number of vent spews varies based on the design and size of the tires. But the presence of tire hair is universal. They are nothing more than remnants of the intricate process that makes strong and durable tires that safely carry you around town every day.
Why do tires have hairs?
These vent spews might seem insignificant, but they serve a key purpose in ensuring tire quality and safety. During the vulcanization process—when raw rubber is molded and cured—excess rubber and any trapped air must escape to prevent flaws. “Each mold is specific to the tire size and type that is being made,” says Robbins. “As the pattern is pressed into the tire’s rubber, the extra or unnecessary rubber requires a way to escape the mold.”
The solution: Each mold includes tiny pinhole vents that serve as escape routes. The rubber that seeps into these vents forms the thin, hair-like strands on the tire surface.
So why do new tires have hairs? It’s all about quality control. “They help to ensure that there are no trapped gases or air bubbles in the tire that could compromise its structural integrity and performance,” says Margarette Stine, automotive expert at 4WheelOnline. These small rubber whiskers are a visible sign that the tire mold is working as intended—releasing pressure, reducing imperfections and contributing to a safer final product.
Why don’t manufacturers remove the tire hairs?
Essentially, the ventilation of air and an excess of rubber during molding is a telltale sign that a tire has been produced without defects. These tiny strands become markers for a well-honed process of manufacture. If they are visible, it means that this particular tire has undergone thorough shaping and quality assurance steps.
Of course, car owners sometimes see them a little differently. Despite their harmless nature, tire hairs often spark confusion or concern. A common myth is that these rubber bristles are performance indicators or traction enhancers, when in reality, they serve no functional purpose once the tire leaves the factory. Some drivers even believe that the presence of tire hairs means the tire hasn’t been used or tested properly. Understanding that these vent spews are purely cosmetic can ease your worries.
How do tire hairs affect driving and safety?
They don’t have any effect on safe driving. Because they’re found on the part of the tire rubber that doesn’t hit the road, they have no impact on how well your tire grips the pavement in rainy weather or the overall comfort of the ride, Stine says. These rubber hairs also don’t have any impact on road noise or why your tires squeak when you’re driving.
But remember: They actually serve as subtle indicators of quality assurance during production, signaling that a new tire has entered the world without defects.
Should you remove tire hairs?
You can if you want to, but there is no functional reason to do it. Whether you’re buying the most affordable tires on the market or you recently snagged the tires that car experts buy, tire hairs are simply byproducts of the manufacturing process. If you’re inclined to trim or remove those rubber whiskers for aesthetic reasons, you can do so with extremely sharp scissors or use a fine abrasive tool to shave them off, suggests Stine.
But be careful! You want to avoid cutting into the tire rubber. Those black spines may seem insignificant, but damaging the underlying tire surface can compromise the structural integrity of the tire or impair its performance, which means that, at best, you’ll need to shell out more money to replace a tire. At worst, you could have an accident. But says Stine that“as long as the process of removing the tire hair is executed with precision, your tire will not be exposed to unnecessary risks.”
What should you do if your tire doesn’t have these rubber hairs?
Once you’ve learned why tires have hairs, your natural reaction may be to wonder—or even feel a little nervous—about a lack of the rubbery filaments.
Good news: You probably don’t need to sweat it, especially if yours is a used car. They are naturally worn away during normal driving, says Robbins, and the presence or absence of these hairs doesn’t really determine if a tire is safe. It’s far more important to regularly examine your tires for signs of wear and tear, such as reduced tread depth, cracks or bulges.
When it comes to buying new tires, however, the presence of these little rubber spikes or fine bristles can be an indicator of the tire’s quality. New tires are often covered with these small, noticeable strands, a sign the tires have not been driven. There is one instance where the lack of tire hairs can be a tell: It could be a sign that the tires are worn, old or in need of replacement. Part of being a responsible car owner means monitoring the health of your tires closely and regularly. Refer to your car manufacturer’s guidelines for when and how often your tires should be replaced.
FAQs
Can tire hairs indicate whether a tire is original or counterfeit?
The short answer is no. Since tire hairs are a byproduct of regular manufacturing, you cannot use them to differentiate originals from counterfeits. Counterfeit tires may very well have vent spews if they were produced using molds that imitate legitimate manufacturing techniques.
Do tire hairs affect tire balance or alignment?
Tire hairs have nothing to do with wheel balancing and vehicle alignment. They are just byproducts of the tire-mold process and are located on portions of the tire that do not touch the road.
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Sources:
- Will Robbins, executive director of strategic and product portfolio planning at Bridgestone Americas
- Margarette Stine, automotive expert at 4WheelOnline
