A vehicle’s wheels are far from simple components. Several components must be integrated together to create a functional wheel, and the design of these components requires a lot of complexity.
Wheel bearings are critical for your wheels to work together—specifically, for the hub, tire and assemblies to work harmoniously. They’re also prone to abuse, which is why it’s essential to know the warning signs. But before we go deeper into bad bearings, symptoms and impact of these problems, it’s equally important to understand what they are.
What is a wheel bearing?
Wheel bearings are made up of several steel balls held together in a metal ring called a race. In your car’s wheels, there is a hollow piece of metal at the center of each wheel called a hub. The wheel bearings fit tightly inside this hub, and ride on a metal axle shaft, helping reduce friction when the wheel spins.
Wheel bearings are different from engine bearings because there is no constant source of lubrication for them, and so they must be tight enough to keep away water and road dust. Wheel bearings also support the entire vehicle weight while driving, which is why they suffer a lot of abuse from rough roads and potholes.
As with most automotive components, the wheel bearing can eventually wear out and may need to be replaced. When should you get a wheel bearing replacement? There are several warning signs that can signal that your vehicle needs to have its wheel bearings looked at by an auto repair professional.
How to Tell If The Wheel Bearings Go Bad?
The most common type of wheel bearings used today are ball bearings. Other types include tapered roller bearings, mainly used for trucks, and precision ball bearings, designed for intense radial loads. Regardless of the type your vehicle has, the warning signs are the same: a bad wheel bearing sound.
Below are a few things you ought to keep in mind:
- The most common, and most easily identifiable, symptom of a bad wheel bearing is an audible one. If you hear grinding or grating noises coming from your wheel or tire, note that this is very likely caused by a bad wheel bearing—especially if the noise gets louder as the vehicle accelerates.
- Loose steering can be difficult to convey, but basically, it refers to steering your car and finding that it seems less responsive or less precise than usual. Looseness can be due to a problem with the wheel bearings, but not always. Sometimes the wheel bearings can become worn down, which causes them to loosen within your wheel assembly.
- A related phenomenon is pulling. When you drive, do you feel like your car goes where you tell it to or does it seem to have a mind of its own and veer in a particular direction? Again, this is not always because of a problem with the wheel bearing, but that can certainly be a culprit.
- Finally, be sure to keep an eye on your tires’ wear. Rotating them regularly can help prevent uneven wear, but if you see that they’re wearing out quickly in some spots and not others, it could be a sign that the wheel bearings need attention.
How To Understand a Bad Wheel Bearing Noise?
Squealing & Growling
A bad wheel bearing makes cyclic chirping, squealing and/or growling noises. The pitch of the sound varies with vehicle speed—if it gets louder with every turn or disappears every now and again, you’re probably dealing with a faulty wheel bearing.
Noise coming from a vehicle is a common reason for concern. To avoid misdiagnosis, it’s important to differentiate between the different types of noise caused by various issues. For example, humming could be caused by either worn tires or wheel bearings or CV joints.
Rear Differential Noise vs Wheel Bearing Noise
Loose pinion-bearing preload can be indicated by a howling noise that occurs solely during deceleration. If the howling happens under acceleration at different speeds, then it’s probably worn out gears; however, overly worn out bearings tend to make a howling noise as well when they don’t support the gears correctly. They also tend to make a rumbling sound when turning.