Removing wheel bearings

Bearing location

The bearings are located in the wheel hub on disc-brake wheels, and inside the brake drum, which forms part of the hub, on drum-brake wheels.

Non-driven wheel bearings - the front-wheel bearings of rear-wheel-drive cars and rear-wheel bearings of front-wheel-drive cars - are similar in design, differing only in detail.

They may be either tapered roller bearings or ball bearings . Both types need regular adjustment (See Adjusting wheel bearings ) and lubrication with grease.

Routine lubrication intervals are normally given in the car service schedule. They are usually very long typically three years, 36,000 miles or 60,000 km. But you may need to repack bearings earlier if a routine check shows that the grease is dirty.

Eventually, however, bearings may wear out. A worn bearing becomes evident in various ways. There may be excessive play, which adjustment fails to cure. The bearing may be noisy, especially when cornering.

Roller bearings with a spacer

Roller bearings are usually on driven wheels, with the hub nut tightened to a high torque. A spacer tube keeps the bearings apart.

The noise may be a low-pitched droning at first; then, as the bearing wears more, a scraping sound; finally, just before it seizes , a high whine.

Other signs of bad wear are the steering wandering or pulling to one side, shuddering or squirming during braking.

Replace a worn or damaged bearing as soon as possible.

Bearings are dismantled for greasing, so the procedures for lubrication and replacement are similar.

Before either job, see that you have new grease seals for the bearings.

Loosen the wheel nuts of the two wheels you are dealing with, raise the car and support it on axle stands. Chock the other two wheels.

Release the handbrake if it works on the raised wheels. Take these wheels off.

Dismantling the hub

Support the brake caliper if it is connected to its hose. Pull off the thrust washer and outer bearing.

Remove the dust cap and loosen the hub nut by the same method as for adjustment (See Adjusting wheel bearings ).

If a disc brake is fitted, move the caliper clear of the disc (See Renewing disc-brake pads ) so that the disc and hub can be pulled outwards.

Tie up the caliper so as not to strain the brake hose , if it has not been disconnected.

On drum brakes , if the drum is separate from the hub, take off the drum (See Renewing drum-brake shoes ). If the brake drum is not separate from the hub, it can be removed once the bearing is released.

Unscrew the hub nut completely. Take off the large thrust washer under it to expose the outer bearing. If this is a tapered roller bearing , it will probably fall out (but if it does not, leave it in place).

You should be able to pull off the hub or the hub-drum assembly by hand. If not, give it a few blows with a soft-faced hammer.

Releasing the inner bearings

Prise out the grease seal.

Turn the hub outer side down and use a screwdriver to prise out the grease seal, noting which way round it is fitted.

Take care not to scratch the seating into which the seal fits . Discard the old seal.

If the inner bearing has come away with the hub, lift it out and SE it aside. If it has stayed on the spindle , free it with a few gentle taps of a soft-faced hammer.

In many hubs there is a spacer ring between the two bearings. Put this with the other detached parts.

With ball bearings, the inner and outer races of both bearings stay together when the hub comes off.

Prise out the grease seal from the inner side of the hub as described above.

Separate the inner race of each bearing by driving it outwards from the middle of the hub.

Tap out the inner races

Use a flat-faced punch passed through one bearing to rest against the inner face of the other. Give the punch gentle blows with a heavy hammer, moving it around the outer casing until it comes free.

Some of the balls may drop loose, but most of them will stay embedded in the grease. Extract any spacer between the bearings.

A car’s wheel is one of the crucial parts of a vehicle that helps in safe transportation and smooth drive. However, several wheel components make it operational and aid in properly turning wheels. One of them includes wheel hub assembly, without them, your wheel won’t move. Read on to find more about wheel hub assembly, its location and purpose.

What is a Wheel Hub Assembly?

A wheel hub assembly is also referred to as wheel hub bearing, hub assembly and wheel hub unit. The hub assemblies attached to the wheel of a car helps in moving a vehicle smoothly. They also impact the performance of the anti-lock braking system and fuel economy. Hence, to ensure that the performance of a car is great, all these car wheel parts should function together with ease. 

Where Wheel Hub Assembly is Located?

You can find the hub assembly by removing the car’s wheel

A car hub assembly is placed between the drive axle and the brake drums or discs. The hub assembly is attached with the bolts on the brake disc side; whereas, it is mounted to the steering knuckle from the drive axle’s side. You can also find a wheel hub unit as a bold on or pressed in assembly.

You can locate the hub assembly by removing the car’s wheel,  the brake calliper and the brake rotor. 

What is the Function of Wheel Hub Assembly?

The hub assembly is responsible for rolling the vehicle’s wheels, that is, it makes the CV joint transmit the proper torque to the wheels and set it in motion. However, this component can be coupled with nuts and bolts to the brake drum, forming a single robust and compact piece.

The wheel hub assembly is also an essential part of your anti-lock and traction control system. The hub assemblies also contain the speed sensor that helps in controlling the ABS. 

This is a fundamental component for traffic safety. Although it is a component with long service life, several problems can damage the wheel hub, such as knocks, falls into holes or unevenness in the road and water infiltration by traffic in flooded regions.

Symptoms of Bad Wheel Hub Assembly

Poor braking can be one of the reasons for bad hub assembly

Several symptoms of wheel hub failure  can alert you to a problem with your wheel:

• Poor braking: You need to push hard on the pedal to apply the brakes.
• Lack of Steering Response: Your steering is loose or shakes while driving. 
• Suspicious hub noise: You hear a grinding, whirring and squealing noise coming from your wheel hubs.
• ABS warning light: You will see an ABS warning light on the dashboard 

If you are experiencing any of these issues, your car hubs may need to be changed soon. It is important to note here that the average lifespan of a hub is 400,000 km for old cars and 100,000 km.

Wheel Hub Care

Since it is a resistant and long-life part, it is often ignored while making a car maintenance schedule. However, it is essential to pay attention in some driving situations that can cause damage to the wheel hub units:

• Severe bumps at high speeds
• Passing holes or uneven slopes
• Wheel crashes into the curb
• Contamination of water 

Can I Drive with a Damaged Wheel Hub Assembly?

You shouldn’t drive a vehicle with a bad hub assembly

Driving with a faulty wheel hub assembly can be dangerous. This can ultimately lead to the failure of traction and the ABS. Also, your vehicle can become shaky and your car might become unstable because of the loose wheels. In addition, a bad wheel hub assembly also put a lot of pressure on the CV joint, hub and the car’s transmission. In some situations, it also causes the wheel to come off. 

Hence, if you suspect that your car’s wheel hub assembly is failing, take it to the nearest mechanic for service. In case you are planning to buy wheel hub assemblies and other wheel parts in the UAE, then check dubizzle. 

With this, we conclude our guide on all about wheel hub assemblies. If your car parts are getting worn out and need costly repairs then consider buying a used car in the UAE at market competitive rates.

If you find this guide informative, stay tuned to the UAE’s top auto blog for more.