Blog Post

Replacing a wheel bearing: A complete guide

Wheel bearings play a vital role in the safety and performance of a vehicle, although they are often overlooked by drivers. In fact, these components are responsible for the smooth, frictionless rotation of the wheels, ensuring a safe and stable ride. However, over time and with use, wheel bearings can wear out and compromise the vehicle’s safety and handling. That’s why you need to recognise the signs of wear and know when it’s time to replace them.

In this comprehensive guide, we aim to provide a complete overview of wheel bearing replacement. Our aim is to enlighten you as to why replacement is necessary, what wear indicators to look out for and the detailed step-by-step process for carrying out this operation. Whether you’re an experienced mechanic or a novice to car maintenance, this guide will take you through all the necessary steps to ensure the safety and optimum performance of your vehicle.

What is a wheel bearing?

Wheel bearings are essential components in a vehicle’s wheel assembly and play a fundamental role in car mechanics. These often discreet but useful devices are designed to allow the wheels to rotate smoothly and efficiently, ensuring optimum vehicle performance.

Wheel bearings, definition

Wheel bearings are mechanical components integrated into a vehicle’s wheel assembly, playing a decisive role in vehicle mobility and performance. Their main function is to enable the wheels to rotate smoothly and without friction while supporting the vehicle’s load. These devices are generally made up of balls or rollers arranged between two concentric rings, creating a mobile interface between the fixed part of the axle and the rotating part of the wheel.

Their role in wheel assembly is to facilitate rotation and to reduce friction between the surfaces in contact, thereby promoting stable, efficient driving. Wheel bearings are installed in the wheel hubs, allowing the wheels to rotate freely while maintaining a solid connection with the axle.

How wheel bearings facilitate tyre and wheel rotation and their impact on handling and speed 

Wheel bearings facilitate tyre and wheel rotation, which has a direct impact on a vehicle’s handling and speed. These components are designed to reduce friction between the moving parts of the wheel assembly, ensuring free and unhindered rotation.

The bearings make a significant contribution to the vehicle’s manoeuvrability and make it easier for the tyres and wheels to rotate. They reduce rolling resistance for a more stable ride, reduce vibrations and improve road grip. This contribution to roadholding is useful in ensuring optimum handling, especially in varied road conditions.

Wheel bearings also have a significant impact on vehicle speed. Bearings in good condition allow the wheels to rotate smoothly and efficiently, promoting constant speed. These components eliminate unnecessary friction for optimum performance, both in terms of acceleration and maintaining speed, which has a direct impact on the vehicle’s fuel efficiency.

Why replace a wheel bearing? 

Changing a wheel bearing has a number of advantages in terms of your vehicle’s durability. Here are a few examples of the benefits:

Reasons for bearing wear and failure 

Wheel bearings, although designed to withstand considerable stress, are subject to wear and failure due to a variety of factors. Normal wear results from daily use of the vehicle and the accumulation of mileage. Repeated mechanical forces exerted on bearings over time lead to progressive deterioration of their internal components, affecting their ability to maintain smooth, friction-free rotation.

Impact damage is another significant cause of premature bearing wear. Impacts from potholes, bumps or even collisions can cause bearings to deform, crack or break. This structural damage compromises their optimal operation, jeopardising the vehicle’s stability and safety.

Water intrusion is also a major factor contributing to accelerated bearing wear. Water can penetrate bearing components, corroding internal surfaces and altering the lubrication that is the basis of proper operation. This is of particular concern in damp environments or when crossing flooded areas.

The importance of timely replacement

The timely replacement of wheel bearings is of great benefit to road safety and the preservation of vehicle integrity. Defective bearings considerably increase the risk of accidents, as they compromise the vehicle’s stability and manoeuvrability. Sudden bearing failure can lead to loss of control, endangering the driver, passengers and other road users.

As well as reducing the risk of accidents, timely replacement helps to maintain the overall mechanical integrity of the vehicle. Degraded bearings can lead to widespread damage to other components in the bearing system, amplifying repair costs. Vehicle owners can avoid unnecessary expense while preserving the reliability and durability of their vehicle if they can act preventively and replace wheel bearings before they reach a critical condition.

Timely replacement helps to maintain optimum vehicle performance, ensuring smooth wheel rotation, stable roadholding and safe driving. It also helps to minimise unscheduled downtime, avoiding potentially dangerous situations on the road.

Recognising the need for replacement 

Recognising the signs of a worn wheel bearing helps to ensure a vehicle’s safety and optimum performance. Several indicators can alert drivers to the imminent need for replacement.

Squealing noise while driving 

Squealing noise while driving is a significant indicator of a worn wheel bearing. This metallic, persistent sound occurs when bearings experience excessive friction, usually due to wear or damage. This noise, often described as a high-pitched whine or metallic squeal, may be more audible at higher speeds. Ignoring this sign can lead to continued deterioration of the bearings, compromising the safety and performance of the vehicle.

Unusual vibrations or shaking

Unusual vibrations or jolts, particularly felt at high speeds, often indicate worn wheel bearings. These vibrations result from asymmetry in wheel rotation, compromising vehicle stability. If the steering wheel or chassis exhibits abnormal shaking, this may indicate a bearing failure. If neglected, these symptoms can affect vehicle handling and lead to safety problems.

Loose steering or difficulty maintaining alignment

Loose steering or difficulty maintaining alignment can be the result of worn wheel bearings. Failures in these components can lead to directional instability, causing a loose steering feel or difficulty in maintaining direction. These signs compromise the vehicle’s manoeuvrability, increasing the risk of accidents. When unstable steering is detected, defective bearings must be replaced quickly to restore stability and ensure safe driving.

Irregular tyre wear 

Uneven tyre wear is a common indicator of defective wheel bearings. Worn bearings can lead to uneven weight distribution on the tyres, causing asymmetric tread wear. Regular tyre inspection can identify these abnormal wear patterns, signalling the need to replace the bearings. Ignoring this indication can lead to premature tyre wear, compromising safety and overall vehicle performance.

Decreased steering response

Reduced steering response is a worrying sign of wheel bearing failure. A delayed or diminished response to steering wheel movements indicates a potential problem with wheel rotation, compromising vehicle handling. This reduced responsiveness can create dangerous situations, requiring rapid intervention to avoid serious consequences.

How these signs affect driving safety

These signs of a defective wheel bearing can considerably compromise driving safety. Squealing noises, vibrations, loose steering, irregular tyre wear and reduced steering response signal potential problems which, if ignored, can lead to loss of vehicle control, accidents and critical failures. A direct impact on handling and stability requires rapid intervention, underlining the importance of preventive bearing replacement in maintaining safety on the road.

The replacement process

Replacing a wheel bearing, although technical, can be done successfully by carefully following each step of the process. Before you start, make sure you gather tools such as a jack, jackstands, ratchet spanner, sockets, rubber mallet, vice grip, torque spanner and screwdriver set. These tools are used to get the job done efficiently.

To ensure your safety throughout the process, don’t forget to wear personal protective equipment such as gloves and goggles. Start by raising the vehicle safely using the jack, placing the jackstands, and removing the wheel using a ratchet spanner. Next, dismantle the brake calliper by removing the bolts. Before proceeding to the rotor, determine the type of bearing used in your vehicle, as this will guide the subsequent steps. After identifying the bearing type, continue by removing the rotor by disengaging it from the axle.

Disconnecting the wheel hub involves removing the nuts and bolts that secure it to the axle. When removing the old bearing, use a vice-grip carefully to avoid damage. When installing the new bearing, make sure it is correctly aligned in the housing provided.

Reassembly of the wheel hub follows this step, with the nuts and bolts firmly tightened. Then return to the brake calliper and rotor, reinstalling them and tightening the bolts accordingly. Carefully lower the vehicle and tighten all the nuts and bolts with the torque spanner to the recommended torque specifications.

On completion, carry out a test drive to confirm that the bearing is operating correctly. By carefully following these steps along with the appropriate safety advice, wheel bearing replacement can be successfully completed, ensuring your vehicle’s safety and optimum performance on the road.

Professional advice for a successful replacement

Successful wheel bearing replacement depends on a number of factors that require a professional, precise and careful approach. Choosing the right replacement bearing is fundamental. Choose a quality part that meets the specifications recommended by the vehicle manufacturer. The compatibility of the bearing with the model and year of manufacture will ensure optimum operation.

Installation must be carried out with particular care. Strictly observe the recommended torque specifications for each nut and bolt. Use of a torque spanner is imperative to avoid tightening errors that could compromise bearing performance.

Carefully check other related components for damage or excessive wear. Items such as seals, ABS sensors or other parts related to the bearing system should be inspected to ensure total system integrity. Bearing replacement provides an ideal opportunity to check the general condition of surrounding components.

If in doubt, it is strongly recommended that you seek professional help. Experienced mechanics have the expertise to identify potential problems, make accurate diagnoses and ensure a trouble-free replacement. The complexity of the bearing system and its direct impact on the safety of the vehicle mean that it is important to consult a professional if you have any questions or uncertainties.

Cost of rear bearing replacement

The cost of rear bearing replacement varies according to a number of key factors, and you need to understand these in order to plan financially for this operation. The type of vehicle is the first determining factor, as top-of-the-range or specific models may require more expensive parts. In addition, the geographical location of the bearing on the vehicle can influence costs, with some bearings being more accessible than others.

When you consider having the replacement carried out by a professional, the cost includes not only parts but also labour. On average, a rear bearing replacement by a professional mechanic can cost between CHF150 and CHF400, depending on the complexity of the job and local labour costs.

If you opt for a DIY project, costs can be reduced, but this depends on the accessibility of the bearing and your mechanical skills. Replacement wheel bearing kits typically cost between CHF50 and CHF150, but you need to add the cost of the specific tools required for your project.

Investing in timely wheel bearing replacement can save you money in the long run. Ignoring the signs of failure can lead to more serious damage to other components in the bearing system, thereby increasing repair costs. In addition, faulty bearings can compromise vehicle safety, increasing the risk of accidents and generating unforeseen expenses.

Ultimately, the decision must take into account the type of vehicle, the location of the bearing, the choice between professional or DIY, and the value attached to the vehicle’s safety and performance. A proactive approach can not only ensure safe driving but also contribute to long-term financial savings.