Diagnosing that wheel bearing noise

Wheel bearings are a fundamental part of your wheel that connect it to the axle. They’re made from steel balls that sit inside a ring called a race, and help reduce friction and wear as you drive. They support the whole weight of the vehicle, so they’re pretty important!

If your wheel bearings aren’t in top condition, they can affect your brakes and make your car unsafe to drive. That’s why it’s important to know how they work, how to diagnose problems, and know quickly if you have a bad wheel bearing.

What are the signs of a bad wheel bearing?

Being aware of how your car sounds, and any changes in handling, means you can get on top of issues when they arise. As wheel bearings are a moving part that connects the wheel to the axle, there are some obvious signs that can indicate a problem. Here’s some specifics you should watch out for:

• A humming noise in the car getting louder with speed: This can happen when the bearing isn’t properly lubricated. The bearings rub on the race and create a humming, grinding, or squealing noise, so if it gets louder as you accelerate, it’s probably your wheel bearings.
• Wheels are wobbling: If you notice that your wheels are wobbling excessively, it could be your bearings. If you jack your car up you’ll be able to assess how much play there is in the wheels. If there’s more than a bit, you’ll need to get it fixed ASAP by a qualified mechanic.
• Vibrating steering wheel: This can happen for a few different reasons, one of which is your wheel bearings going bad. Water may have entered, or the race or balls could be worn. The vibrations will usually be worse when you’re driving slowly.
• Hot wheels (no, not those ones!): Although there’s always some heat coming off your wheels, if you notice your wheels are red hot, that’s not normal and is likely due to excessive friction caused by bad bearings. It could also be your brakes, but whatever the cause—it needs to be repaired quickly to avoid an accident.

How to test which wheel bearing is bad

It’s rare for all your bearings to go at once, so how do you know which one is the bad one? Luckily, there are a few ways to tell before you call a mechanic:

• If you hear a humming noise, you can usually pinpoint where it’s coming from by listening carefully.
• By inspecting the tyres, you can see if one is worn unevenly. All tyres wear over time, but if one looks markedly different from the others, that’ll be the culprit.
• If the vehicle pulls to the side when braking, the side that it pulls to will have the faulty bearing.
• You can also jack the car up and check how the wheels feel. Are they easy to spin? If not, that indicates a bad bearing. Excessive movement in the wheels will also indicate a bad bearing, and you can test this by pulling on them from the side. Too much play and it’s definitely a bad bearing.

How long will a wheel bearing last after it starts making noise?

Although wheel bearings may seem like a small thing, it’s crucial for them to be functioning properly. If you don’t take your car in at the first sign of trouble, you risk your wheels seizing up, or even worse, completely shearing off. Driving with a bad wheel bearing is dangerous to you and other drivers, and could easily cause an accident, so it’s best to get them replaced as soon as possible.

However, if you’re in the middle of nowhere and absolutely have to drive as you’ve no other option, drive slowly and you should get about 1500km before the bearing fails completely—hopefully long enough to get it to the closest local workshop!

What to do when you’ve got a wheel bearing noise diagnosis

So you think you’ve got a bad bearing, now what?

In most cars, the bearings are sealed, so you’ll need to replace the whole thing. But if you’ve been diligent and tackled the problem early, there shouldn’t be any other issues.

Wheel bearing replacement can be tricky though, as they need to be sealed tightly against the wheel hub. It’s best to get it done by a qualified mechanic to have peace of mind, and avoid more problems down the road.

How much to replace a wheel bearing?

A wheel bearing replacement should cost between $300-$700 depending on the make and model of your car, and which bearing has gone. Rear hub bearings used by some manufacturers can cost more for parts for example, and in front wheel drives the front bearings are more tricky to replace.

Need more advice on your wheel bearings, or need to book a service? Call one of our qualified mechanics today and they’ll be happy to assist you with any questions you have!