You’re driving along on a warm, sunny day listening to your favorite song. Life is good. But when you turn down the radio, you hear an unusual noise that coincides with the rotation of the tires. What could it be?
A bad wheel bearing is one possibility.
What Does a Bad Wheel Bearing Sound Like?
Most people describe a bad wheel bearing as making a growling or rumbling noise (the sound is often mistaken for worn tires). Also, in some cases, a bad bearing may make a high-pitched grinding or squealing sound.
In either case, the frequency of the sound will correspond to the rotation of the tires. The sound will also increase with vehicle speed (though it may go away at a certain point) and may get louder when turning in one direction or the other.
How to Tell if Your Wheel Bearing is Bad
Your car has a lot of rotating parts, which makes it hard to distinguish a bad wheel bearing from many other problems. Paying attention to when the noise occurs may help you narrow down your options.
Obviously, a faulty wheel bearing will only make noise when you’re driving. So, if you hear the sound when the vehicle is stopped, you can rule out the wheel bearings altogether. It’s also important to note that wheel bearing noise will basically sound the same no matter what type of surface you’re traveling over.
Tire noise, however, will usually change with the road surface.
Furthermore, in most cases, you’ll hear a noisy wheel bearing regardless of whether you’re accelerating or decelerating. On the other hand, some drivetrain noises—but not all—will change upon acceleration or deceleration.
At the end of the day, it can be difficult to distinguish a bad wheel bearing from other problems. That’s why it’s important to perform further diagnostic work before jumping to conclusions. Otherwise, you may end up replacing a wheel bearing only to find the problem was something else.
You’ll also want to keep in mind that not all bad wheel bearings make noise. Some worn-out bearings will exhibit excessive lateral movement, without making any abnormal sounds.
How to Check for Bad Wheel Bearings
There are a lot of other problems that can mimic the sound of a bad wheel bearing. To be sure that one of your car’s wheel bearings is to blame, you’ll need to do some additional diagnostic work.
Some of the methods used to pinpoint a bad wheel bearing include:
- Checking for play by rocking the wheel/tire assembly
- Inspecting for roughness
- Listening for noise with a stethoscope
- Monitoring for excess heat
- Checking for play using a dial indicator
To learn more about each of these methods, check out our in-depth article on diagnosing a faulty hub and bearing assembly.
Signs of Wheel Bearing Failure
You already know a faulty wheel bearing can cause noise. But did you know that it can cause other issues as well? A bad bearing may allow the wheel hub to exhibit excessive movement. Plus, the internal bearing components will experience increased friction. As a result, you may notice your vehicle displaying the following problems:
- Growling/humming noise
- Vibration when driving
- Pulsation when braking
- Irregular or abnormal tire wear
- Illuminated warning lights
If you’d like to know more, read our article on wheel hub assembly symptoms.
Can You Drive with a Bad Wheel Bearing?
You might be wondering whether you can continue driving with a bad wheel bearing. And the answer is—absolutely not. In some cases, a failed wheel bearing can cause you to lose a wheel while driving, which can have potentially deadly consequences.
So, if you think you hear the rumble of a bad wheel bearing, be sure to get your vehicle repaired immediately. Your safety depends on it.
What Can Happen if You Have a Bad Wheel Bearing?
As was mentioned above, if you ignore a bad wheel bearing, you could end up losing a wheel. That’s the worst-case scenario, but there are other undesirable consequences, as well. A bad wheel bearing can cause abnormal tire wear, a pulsation while driving—even problems with the ABS system.
So, once again, if you think you’ve got a bad wheel bearing, get the problem fixed right away by either going to a mechanic, or by purchasing a replacement bearing and fixing it yourself.