What are wheel hubs and wheel bearings? Both use the same physical characteristics of a bearing, in that they contain bearing balls that are lubricated to rotate and thus make the wheel turn. A major difference between the two is how they are assembled. Wheel bearings can be taken apart, lubricated and reassembled to be used again. Hub bearings are pre-packaged at the manufacturer's factory and are sold and installed as a complete unit. These cannot be taken apart for re-lubrication but must be replaced.
Wheel hub
Wheel hubs are not visible at first glance unless you remove the wheel. A wheel hub is used to connect any wheel to the vehicle, more specifically to attach the wheel to the drive axle. The wheel hubs are thus a vital part of the wheel assembly that allows the driver to drive the vehicle. It is therefore very important that they work correctly. If problems occur, the wheel may become unbalanced and difficult to control, causing steering alignment problems. Clearly, this will make driving the vehicle more difficult and can create dangerous situations.
The wheel hub also plays a crucial role in the car's anti-lock braking system (ABS) and traction control system (TCS).
The hub is driven by a shaft running from the final drive. The shaft has a flexible joint (usually a constant-speed joint) at each end to allow steering and suspension movements.
The end of the drive shaft runs through the centre of the hub carrier and engages with the rotating part of the hub. When the drive shaft rotates, the rotating part of the hub rotates with it.
Wheel bearing
Like the wheel hub, the wheel bearing is also indispensable in the car's suspension. The wheel hub and wheel bearing are connected, in many cars these are separate parts. However, it is increasingly common for the wheel bearing to be fitted directly with a wheel hub. However, this depends on the make and type of car.
If we look at a wheel bearing, it consists of 2 rings. These rings lie around each other and can move separately from each other with the help of balls or rollers. In this way, it allows the wheels to turn.
Driving with a missing or defective wheel bearing is dangerous. If your car shows any of the symptoms of a worn bearing, it is best to seek out a reliable workshop. If wheel bearings become detached from the vehicle, it can create a very dangerous situation on the road. Wheel bearings play a vital role in keeping the wheel attached to your vehicle. Without wheel bearings, the wheel is essentially unattached. This can be very dangerous, especially when driving at high speeds on the highway. Losing a wheel can lead to loss of control of the vehicle, putting yourself and other drivers at risk.
There are different types of wheel bearings a manufacturer can use. Here are some common types with their main purpose.
Ball bearings
Of all the wheel bearings out there, ball bearings are the most common and versatile wheel bearings that can be used. The purpose of a ball bearing is to reduce rotational friction and support radial and axial loads. It achieves this by using at least two rings containing balls and transmitting the loads through the balls. In most applications, one bearing ring is stationary and the other is attached to the rotating assembly (e.g. a hub or shaft). When one of the bearing rings rotates, the balls also rotate. Because the balls are rolling, they have a much lower coefficient of friction than if two flat surfaces were sliding against each other.
Precision ball bearings
The design of precision ball bearings makes them suitable for high-performance use. Precision ball bearings have the ability to minimise friction, which in turn reduces the amount of heat produced.
Roller bearings
Roller bearings are a type of wheel bearing that are commonly used. Only, roller bearings are not as versatile as ball bearings. Roller bearings are good at handling weight, but they are not the best for curves.
Tapered roller bearings
Common wheels on cars and trucks usually have tapered roller bearings. They have a cone shape that reduces friction when cornering because the pressure load is high.
Wheel bearing replacement
Is it easy to replace a wheel bearing at home? This depends on whether it has a connection to the drive shaft. Bearings without drive shafts are often easier to replace.
Replacing a wheel bearing that comes with the hub and bolts to the axle or steering knuckle is not very difficult if you have the right skills, tools and the manual. Of course, the large axle nut is very tight and can be difficult to remove and the caliper also needs to be removed. If the bearing needs to be pressed in and out, it is best to leave that to the pros.
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