Wheel bearings play a crucial role in the drivetrain of any car since they connect the static and moving components of the vehicle.They are specially designed to reduce friction and to promote efficient wheel rotation. However, the bearings operate under a lot of pressure and can eventually succumb to wear and tear. That’s why it’s important to know the tell-tale signs of failing wheel bearings. Here are a few signs to look out for:
Signs Of Bad Wheel Bearing
1. Abnormal side pulling
Normally, unusual side pulling when you step on the breaks indicates a faulty equalizer or caliper, but you cannot rule out loose wheel bearings as the cause. Severe looseness of the wheel bearings can result in excessive run out, which in return can cause brake pulling or pulsating.
2. Feeling loose behind the wheel or unstable on the road
If you drive regularly, chances are you will detect any small changes in the drive quality and responsiveness of your vehicle. This could be as a result of the bearing wearing down, which can make them to become loose inside and sit less snugly in the wheel spindle and hub.
3. Snapping, popping, or clicking sounds
These annoying sounds are commonly caused by a worn or faulty CV-joint and you can hear them when making sharp turns or cornering. However, the sounds could also be caused by excessive bearing endplay, which is mostly associated with poor clamping.
4. Constant chirping sound
Another sign of failing wheel bearing is the constant chirping sound that begins when driving in one direction and increases as you turn or stop. It may also get worse when you speed up and can cause the steering wheel to vibrate too. Basically, the damaged bearing is on the opposite side that is producing the noise and it is a clear sign of damaged bearings.
5. Car grinding or grating while in motion
Grating or grinding sounds are usually heard when turning or shifting and changes with your speed. This kind of noise indicates lack of bearing integrity mainly caused by roller or raceway damage. Moreover, you will still hear the noise when you depress the clutch or apply pressure to the throttle.
6. Abnormal tire wear and tear
If you notice abnormal tire wear whereby the tires on one side are more worn out than the other side, it could be a sign of damaged or excessive looseness in the wheel bearings. However, there are other major causes for tire wear such as misalignment, damaged suspension components, and improper tire inflation.
7. Vibrating steering wheel
If the wheel bearings get excessively damaged, your steering wheel might start vibrating, and could be a sign of bad wheel bearing. The vibration mostly occurs when driving at slower speeds but becomes worse when accelerating the motor vehicle or when you step on the gas pedal. Unbalanced tires can also cause the steering wheel to vibrate at high speed. So you should consult a mechanic to get your car diagnosed.
8. Wobbling or vibrating wheels
This is yet another tell-tale sign of a damaged wheel bearing caused by lack of clamping (or improper clamping) or mechanical damage in the bearings. However, this problem is also associated with worn tires, chassis misalignment, or damaged suspension.
8. Anti-lock braking system lighting up
If the Anti-lock braking system fails, it is an indication of serious mechanical damage. The problem is mainly caused by improper movement due to extreme endplay, which can lead to lack or loss of bearing clamp. Mechanical damage caused by corrosion can lead to the loss or lack of bearing clamp. In case you experience this problem, you need to take the vehicle to an authorized service provider to avoid any problems while driving.
Replacing a Wheel Bearing
All cars need replacement of wheel bearings at some point no matter the model, make, or year. Below are the steps you can use to replace the bad wheel bearing.
Note: Each car is different so the steps given below are general guidelines and may not be fit for all vehicles.
- Park your vehicle on a leveled surface to prevent it from rolling away.
- Secure wheels that you are not planning to replace the bearings using sturdy wheel chocks for added stability
- Loosen the lug nuts gently and elevate the wheel using a jack for proper access to inner areas of the wheel.
- Unscrew the already loosened lug nuts and then remove the wheel.
- Remove the brake caliper’s bolts using a ratchet and a socket, and then remove the caliper with a screwdriver.
- Remove the dust cover, castle nut, and cotter pin and place them in a safe place.
- Remove the rotor.
- Unscrew the hub using a breaker bar or a thin socket wrench and get the hub off the axle.
- Take apart the hub assembly to easily access the bearings.
- Remove the bearing assembly’s races and clean the knuckle.
- Install new races and wheel bearings.
- Replace all other parts in a reverse order.
Cost of replacing wheel bearings
The cost of replacing wheel bearings usually depends on your car model, make, year, and the labor involved. In most vehicles, a wheel bearing comes with a hub to bolt to the spindle or steering knuckle. In such vehicles, it’s pretty easy to replace the bearing and may cost approximately $65-$180 for the parts and $80- $180 for labor.
In other vehicles, the wheel bearing has to be pressed into the spindle or steering knuckle using a press, which involves more labor. It may cost approximately $40-$120 for parts and $120-$250 for labor. In other large cars such as trucks and SUVs, wheel bearing replacement is more labor intensive, thus it is more costly.
How to tell which wheel bearing is bad?
When diagnosing wheel bearing noise, it is quite difficult to tell exactly where the rumbling or growling noise is coming from. This is because the noise is transmitted through the axle, suspension, frame, and to the body of the vehicle. So when the bearings are tested with the wheels unloaded, the sounds normally disappear. Here are the various methods you can use to locate the faulty wheel bearing:
- Grasp the wheel at 6 and 12 o’clock positions and tip it in and out. Typically, ball, sealed and tapered roller bearings should have less than 0.005” end play.
- Place a set of electronic “ears” on each axle assembly to determine the wheel causing the noise.
- Drive the car for a few miles to heat up the bearing lubricant and steer the vehicle fast from side to side in an empty space or parking lot. The noise will increase as chassis weight rolls on the faulty wheel bearing.
Why Do Wheel Bearings Go Bad?
Just like any other mechanical part of your vehicle that can rotate, rub, and roll, wheel bearings are prone to wear and tear. This is mainly because the wheels are rotating while putting a lot of weight on them when driving. As a result, the wheel bearing are put under a lot of stress, which may cause the bearings to become worn out. Here are some of the reasons why your wheel bearings may get worn out or damaged.
Driving across a flooded street
The number one reason why bearings fail or go bad is floods. If you drive in a flooded area, you may experience seal leakage, which allows the petroleum-based lubricant to exit the bearing while dirt and water get in. Such exposure to water can degrade the bearing as well as its inner and outer housing, which can cause the skimming when the wheel is rotating.
Passing through uneven roads
As we mentioned above, wheel bearings are put under a lot of pressure when driving. The more you drive on uneven terrains and roads, the more your wheel bearings become worn out and damaged. As a result, the bearings may develop small damaged areas where some small specs of metal start to break off from the bearing. This can limit their ability to minimize friction for the wheels, which may cause annoying sounds and also reduce their lifespan.
Low quality wheel bearings
A wheel bearing is always under huge pressure. Thus, if your wheel bearings are made of low-quality materials, they will have poor heat treatment, which can cause premature failure and wear.
Poorly installed wheel bearings
Reusing of old accessories like nuts, bolts, seals, split pins, circlips instead of using new ones can cause the bearing to work under unsafe conditions, which can accelerate the wear and risk of accidents.
Unbalanced tires
One of the main reasons why your car needs regular maintenance is to get the tires balanced. If not, unbalanced tires can cause some bearings to endure more stress than others. This can result in noisy and damaged bearings as well as unevenly worn tires.
Car accidents
Car accidents can damage your wheels, which can affect the bearings. The impact of an accident can damage the bearing causing them to malfunction and to produce annoying sounds.
Frequently Asked Questions
What does it sound like when your wheel bearing is going out?
When driving with bad wheel bearings, you may notice strange sounds of rumbling, growling, or humming sounds that coincide with rotation of the wheel. Normally, the sound increases as you increase the speed of your vehicle. The sounds may also change when turning the steering wheel.
How long can you drive on a bad wheel bearing?
Bad wheel bearing is a nightmare to every driver and should be replaced immediately. But if you are in the middle of nowhere, drive at a slower speed to prevent the wheel from overheating. This way, your wheel can still operate for a few more hours. All in all, it is advisable not to go for more than 1000 miles with failing wheel bearing since it might lead to bigger problems.
Can you replace wheel bearings yourself?
It is relatively easy to replace wheel bearings if you have the manual, right skills and proper tools. However, this only applies to wheel bearings assembled together with the hub and bolts to the spindle or steering knuckle. If the wheel bearings need to be pressed in and out, it’s best to let an expert replace them.
Can your tire fall off if you have a bad wheel bearing?
As mentioned earlier, a wheel bearing is designed to allow the tire assembly to rotate while the hub area of the wheel bearing assembly acts as the mounting point for the tire and wheel. As a result, if the bearing is extremely damaged, it can cause the tire to completely fall off.
How long does a wheel bearing last?
Most modern vehicles have a seal on the wheel bearing and can last for up to 100,000- 150,000 miles if properly maintained. For older cars, the wheel bearings may need to be checked after 25,000- 30,000 miles. However, the numbers may differ depending on your car model, make, and year.
Sam is Automole’s editor-in-chief and classic car enthusiast. Sam is studying mechanical engineering at Cockrell School of Engineering, Austin. He also writes for many top automotive publications and appears on the Collecting Cars Podcast.