What Are Car Bearings? – Critical Components

Wheel bearings are critical components in a car. They have to sustain the weight of a corner of the vehicle as well as the rapid rotation of the wheel at highway speeds.

They’re also exposed to harsh driving conditions, such as speed bumps and potholes, which can wear them out faster than normal. Over time, these factors can lead to a number of signs that your wheel bearings are failing and need replacement.



Wheel bearings are a critical component of any vehicle’s motion system. They reduce friction – the “slip” between a rotating vehicle’s wheels. And a stationary axle – by allowing the wheels to spin with very little resistance.

While wheel bearings are the most visible, they’re also used throughout the car. You’ll see them in linear systems, such as seat tracks and trunk lids; in moving parts, such as the gearbox; and on engine components, such as the crankshaft.

A major indicator of a quality bearing is its ability to provide smooth, low-friction rotation at thousands of revolutions per minute. That means a tightly controlled manufacturing process with a smooth ball or rollers of the same diameter and surface finish.

These balls and rollers are usually made from stainless steel, like 52100 (with 1% chromium and 1.5% carbon). They can be heat treated to prevent rusting or to increase their strength and endurance.

Types of Bearings

Plain bearingDepending on materials and construction, PTFE has a coefficient of friction ≈of 0.05–0.35, depending upon the fillers addedGood, provided wear is low, but some slack is normally presentLow to very high – depends upon application and lubricationWidely used, relatively high friction, suffers from stiction in some applications. Depending upon the application, the lifetime can be higher or lower than rolling element bearings.
Rolling element bearingThe rolling coefficient of friction with steel can be ≈0.005 (adding resistance due to seals, packed grease, preload, and misalignment can increase friction to as much as 0.125)Good, but some slack is usually presentModerate to high (depends on lubrication, often requires maintenance)Used for higher moment loads than plain bearings with lower friction
Fluid bearingZero friction at zero speed, lowVery highVirtually infinite in some applications, may wear at startup/shutdown in some cases. Often negligible maintenance.Can fail quickly due to grit or dust or other contaminants. Maintenance-free in continuous use. Can handle very large loads with low friction.

Sealed tightly

They’re also usually sealed tightly to prevent dirt, water, and road salt from contaminating them. This is especially important for bearings that are exposed to harsh driving conditions, such as potholes and rough roads.

If your bearings start to squeak, grind, or growl, it’s probably time for an inspection and replacement. Those noises can be warning signs that your bearings have become contaminated, causing the grease to leak or corrode.

Another common warning sign of poor quality is spalling. This happens when the hard metal in a bearing mixes with the soft steel underneath, forming flakes of steel that peel off the surface.

As a result, your bearings may start to wobble or loosen as they rotate and can damage your vehicle’s anti-lock brake system. This can cause an ABS trouble code to be set.

Wheel bearings are one of the most important mechanical systems in a vehicle, yet they’re often overlooked by drivers and mechanics alike. As a result, you might find yourself in the shop for a wheel bearing replacement much sooner than you expect. If your bearings have been damaged by improper installation or by using cheap, low-quality parts.


Car bearings are safety-critical components designed to sustain radial. And axial loads are caused by the various forces interacting with your vehicle as it navigates the road. As a result, when your wheel bearings fail. You will notice a significant loss of performance that affects the way your vehicle drives.

If you are not sure whether you need to replace your bearings. There are a few things that you can do to help determine their condition. These include examining the vehicle’s steering feel, and listening for noises. That may indicate problems with the bearings, and observing how your wheels roll.

When you have determined that the bearings are bad, it is time to begin the replacement process. The first thing you will need to do is park your car on a flat surface. And shift into Park (if it has an automatic transmission) or gear (if it has a manual transmission).


Drive shaft lock

Next, you will want to remove the drive shaft lock nut from the center hub. This is often secured with a screwdriver, but can also be unstacked by using a special tool.

After removing the lock nut, you can then take your ratchet and unbolt the hub from the spindle. Once you have done that, it is now time to install the new wheel bearings.

The bearings are made from a combination of steel. And alloy metals that have been heating-treated to make them hard, strong, and durable. They are also inspected at several stages of production to ensure. That they have the correct amount of alloy metals and the correct size and shape.

Once you have the bearings, you will need to pack them with grease. The right grease will prevent the bearings from rusting and will also protect the bearings from dirt and debris.

You can use a grease packer, or you can pack the bearings by hand. Should try to work the grease into all of the bearings’ nooks and crevices.

You will need to choose a grease that is made specifically for bearings. This will ensure that you are using the best possible grease for your job. Tier 1 moly EP grease is typically the best choice for this application.


Car bearings play an important role in ensuring that your wheels turn smoothly. They can make a variety of noises that are unrelated to driving. But they can also be an indicator that you need to get your wheel bearings replaced.

A bad wheel bearing can sound like grinding, grating, or even a squeak or whine as it rotates. This can occur due to a variety of reasons, including wear and water entering the bearings.

These noises will usually increase with vehicle speed. Though they might not be noticeable at low speeds or when you’re making turns. If they become worse with your speed and don’t go away, it’s likely a wheel-bearing problem.

There are many different kinds of car bearings. But all have the same basic function: a race that allows circular motion. And is surrounded by rollers or balls that allow the bearing to rotate freely. These parts are manufactured using a process that requires tight control over the manufacturing process.

Housing holds

Once the parts are finished, they’re installed into a bearing housing. The bearing housing holds the races together and contains a cage to keep the balls or rollers in place.

During the manufacturing process, a large amount of pressure is applied to the bearings, as they are put together. This helps to ensure that the balls or rollers are evenly distributed around the races.

Then, the bearings are assembled into housing, where they’re seated in the chassis and bolted down. The bearings are then inspected for damage or defects, and a replacement part is ordered.

When you order a new bearing, be sure to use the recommended replacement for your year, make, and model. It’s also important to check that the replacement is made by the manufacturer of your vehicle.

Having an improperly installed or repaired wheel bearing can cause your tires to wobble, which will affect your gas mileage. It can also lead to other issues with your car’s suspension, braking system, and steering. You’ll need to take your car to the shop as soon as you notice this problem.


Car bearings are very important to the performance of your vehicle. They allow your wheels to turn freely over thousands of miles. Are also essential in protecting your vehicle from potholes and other road conditions.

They also provide your brake drums and discs with a sturdy cushion. So, while you may not think about them often. They are an important part of your car and require regular maintenance.

You can easily spot a bad wheel bearing by listening to the sounds. That it makes and noticing its effects on the rest of your vehicle. For example, if you hear a grinding or grating noise. That gets louder with every drive, this is a sign of a faulty wheel bearing and it needs to be replaced right away.

Another common symptom of a bad wheel bearing is uneven wear on your tires. This could be a sign that your wheel bearings are worn out. And need to be replaced, or it might be a problem with your brakes or tires.

Read more: What To Look For In A Extendable Breaker Bar

Damaged wheel bearing

A damaged wheel bearing can be a very serious issue. Which is why it is critical to replace it as soon as possible. If you ignore the issue, it can result in more severe damage and even an accident.

This is why it is important to follow your vehicle’s maintenance schedule. Typically, you should service your wheel bearings when you change your oil and filter.

If you don’t do this, the grease in your bearings may break down and become less effective. Over time, this can lead to your wheel bearings overheating.

In addition, they can rust. To protect your bearings from rust. You should keep them out of any moist places and away from other metal objects. This will help to reduce the rusting process and save you money in the long run.

If you notice any of these issues with your car, Make an appointment to have them checked by a qualified mechanic. Your local AllTyres Auto Center is ready to help you with this important car repair. Call us at 800-ALLTYRES to book an appointment today.