Correcting a wheel (steering) alignment early prevents stress on the steering system and wheel bearings. It only takes a few minutes at little cost.
What are car wheel bearings? Why are they important, what causes their failure and how do I know when they are damaged?
Wheel bearings or commonly called ‘hub bearings’ are steel balls assembled and encased in an inner and outer circular waterproof and sealed ring packed with grease. They support the wheel hub and allow the wheels to turn with significantly reduced friction and effort.
Wheel bearings are important because they carry the weight of wheels, and allow effortless and unilateral (straight) wheel rotation. Wheel bearings help to keep the wheels properly aligned and the constant velocity (CV) joints turning freely. This is very important for car handling, performance and road safety.
Wheel bearings are usually damaged when we drive fast over rumble stops or speed bumps, a common practice on the highways. Wheel bearings can also be damaged when road salts muddy water or corrosion ingress or get past the seals to contaminate the grease and cause premature wear or seizure of the steel balls encased in the bearing housing. There are symptoms and signs that can help you know when your wheel hub bearings are worn out or due for replacement. Your car has a way of telling you that it’s time to replace the wheel bearings. The common sign is strange noises.
The most common is a humming noise as you drive on the highway. If you have heavy-duty offroad tyres they are notorious for making such noise. Don’t rush to conclude that your wheel bearings are worn out. Squealing and growling which intensifies as you speed up is another sign of worn-out wheel bearings.
Wheel wobble as you drive along is another sign of wheel bearing failure. This is dangerous as extreme or violent wobble can cause wheels to disengage or fall off when driving at high speeds. Steering vibration is another sign of bad wheel bearings. However, you need to make sure your tyres are not damaged with flat patches which tend to cause steering vibration. It should be noted that bad wheel bearings cause uneven tyre wear. Noteworthy is the fact that poor wheel alignment and wrong tyre inflation can also cause uneven tyre wear. Careful inspection of the car wheel hub bearings should be done by a mechanic with the car raised off the ground. It should be easy to identify the damaged wheel bearings.
