Common Symptoms of a Failing Wheel Bearing

If you hear a hum or a growl when you put your foot down, you may have bad wheel bearings. Most of the time, symptoms of bad wheel bearings happen gradually. Because many people wait to take their car in to have the problem diagnosed (after the failure is visible), drivers often find out the hard way how costly it can be to repair wheel bearings.

Before you reach a conclusion, many factors are worth considering. To start, let’s rule out the possibility of an electric issue. Loose wires can cause symptoms like the one you’re describing. There could possibly be a worn CV joint or other drive shaft component. A bad CV joint or drive shaft component will cause a growling noise and loose steering, particularly when a vehicle is turned one way or the other.

It is best to take your car to a trusted mechanic and get their diagnosis. A mechanic will be able to determine the exact problem once they have access to your vehicle.

Of the signs caused by a bad wheel bearing, the low-flying plane style rumble is the most identifiable. Bad bearings slowly deteriorate and start to emit low-frequency groaning noises. These noises can be confused for many engine, transmission, or driveline related issues, so it is crucial to rule out anything else before worrying about wheel bearings.

Another effect caused by bad bearings is what is known as a “brake rotor rub.” This happens when the wear in the bearing is uneven, causing it to rock as the wheel rotates. If the wheel is rotated in one direction, the bearing on that side rubs and the tyre screeches; in the opposite direction the bearing on the other side rubs and the tyre screeches. It is especially noticeable when the wheel is turned from one side to the other.

Of note for bad wheel bearings is that the rotational speed changes the pitch of the noise. As speed increases, noise moves from a rumble to more of a shriek.

Vibration, from failing bearings, can vary from being mildly uncomfortable to downright annoying, depending on severity. Due to the nature of failing bearings, vibrations can be felt heavily in the steering wheel at lower speeds, severe enough to cause discomfort or whole body vibrations at higher speeds. If you notice this kind of vibration, accompanied by a humming noise, there is a good chance your bearing is going bad. Becoming accustomed to the noise level your car naturally runs at is a good idea. Over time, you may notice a slight change in hum level meaning the bearings could need replacing.

You’ll probably recognise some changes in how the car handles. Worn bearings allow the wheel hub assembly to have some amount of play. This would cause the steering to feel slightly slack, especially when cornering at high speeds. When the wear gets worse, you will hear a noise like tapping or even clunking when you brake. This happens because the bearing is loose and allows the hub assembly to move within the housing.

ABS problems occur less frequently, but are important to discuss as well. Contemporary automobiles house a variety of structural components within the wheel assembly. As a result, many modern bearing wheel assemblies incorporate ABS sensors, which may prompt the ABS warning indicator in the event of a failing wheel bearing assembly. If this light is activated, in combination with the vibrations and/or noises above, this indicates a failing wheel bearing assembly and not an ABS system.

Uneven wear can be a knock-on effect too. When a bearing wears to the point of failure, a wheel is able to move in and out slightly more than it should. This movement causes tread on your tyres to wear unevenly and from edge to edge. Sometimes you may notice you are consistently topping up one tyre instead of the others. It may also be due to evidence of patchy wear that you see during your normal tyre inspections. When this occurs, it is important to take the bearing and the suspected causes such as tracking and pressure into consideration.

It’s easy to think you can fix a loud wheel bearing problem later, especially if the car drives OK in all other ways. Over time, however, a neglected bearing problem can turn into a complete seizure. In the worst case, the wheel stops turning and detaches from the hub while you’re driving. This is not just an inconvenience—it’s a potentially dangerous situation, so it’s better to be safe and get any new wheel noise checked out.

If any of these symptoms sound familiar, then the next step would be to take the car to get the wheels put up on a ramp in order for the mechanic to see which wheel it is affected on. After jacking the corners and a road test, play in the wheels will usually become apparent pretty quickly, and also the wheel bearings. The wheel bearings of a car may not be that exciting, but you save money and hassle by listening for these symptoms and acting on them right away and preventing potential large problems from occurring.