Is It Safe to Drive With a Bad Wheel Bearing? Warning Signs Arizona Drivers Shouldn't Ignore
Reviewed by Eric Shepherd, Gemba Automotive ASE-Certified Technician
Some vehicle maintenance items announce themselves, be it a dashboard light, a dead battery, or steam from an overheating engine. When a wheel bearing starts to go bad, it can be so subtle you do not even notice at first and is often confused with road or tire noise.
If you ignore a bad wheel bearing, it can lead to vibrations, steering issues, tire wear, and, in more extreme cases, complete wheel separation. Imagine driving down Loop 101 at freeway speeds and suddenly feeling the steering become unstable because the wheel hub has developed excessive movement. While complete wheel separation is rare, it illustrates why wheel bearing problems should never be ignored for long.
At Gemba Automotive, our ASE-Certified Technicians regularly inspect vehicles throughout Phoenix and the surrounding Valley with noises that drivers have been hearing for weeks or even months.
What Are Wheel Bearings?
Wheel bearings are essential to your vehicle's wheel assembly. In simple terms, they allow your wheel to rotate on the axle shaft. The bearings are comprised of either steel balls, known as ball bearings, or tapered rollers, known as tapered bearings, and are held together by metal rings called races.
Why Are Wheel Bearings Important?
Wheel bearings work to reduce friction and allow the wheels to turn smoothly. When properly functioning, they help you maintain control while driving, which ensures your vehicle is operating safely. If the bearings go bad, the brakes, suspension, and steering system can all suffer significant wear, which can lead to expensive repairs and other safety issues.
Types of Wheel Bearings
There are two different types of wheel bearings used on vehicles. Knowing which one you have can help in maintaining your vehicle. Each design was made to handle radial and axial loads. Radial load is the force pushing from the side of a shaft or a wheel, while axial load is the force pushing along the length of the shaft or wheel.
Ball Bearings
Ball bearings consist of metal rings with small metal balls inside. This design allows for smooth rotation and makes this type of bearing suitable for a variety of vehicles.
Tapered Bearings
Tapered bearings were designed to handle larger radial and axial loads than ball bearings, which makes them ideal for heavier vehicles, such as trucks and SUVs. Tapered bearings are comprised of tapered rollers that are between inner and outer metal races, or rings. The design provides greater durability and support for heavy loads.
What Does a Bad Wheel Bearing Sound Like?
When a wheel bearing has gone bad, it can be noisy. One of the most common complaints associated with bad wheel bearings is the unusual noise coming from whatever corner of the vehicle has the bad bearing.
The noise typically begins as a low humming noise that gradually becomes more noticeable as your speed increases. Because of this, many Phoenix drivers assume that the noise is due to the road or the tires on their vehicle. However, as the bearing continues to get worse, the humming can evolve into other noises:
- Growling noises
- Roaring sounds
- Grinding noises
- Metallic scraping sounds
- An "airplane-like" drone that gets louder at higher speeds
You will most likely notice the noise from a bad wheel bearing when you are driving on smooth roads because there will not be as many outside sounds competing with it. You may notice it most clearly on a smooth stretch of Loop 202 when you turn the radio down and suddenly realize the humming gets louder as your speed increases. If the noise gets louder as you accelerate and quieter as you slow down, a wheel bearing may be the culprit.
Common Wheel Bearing Symptoms
Wheel bearing noise is usually the first thing you will notice, but it is rarely the only warning sign you will experience.
Humming or Growling Noise
While the sound starts subtly at first, it can grow to a growling or humming noise. It can sound like you are driving on aggressive off-road tires even though you are on standard highway tires.
Steering Wheel Vibration
As the wheel bearing starts to go bad, the hub assembly can develop some play. As a result, the looseness will create vibrations that you will feel in the steering wheel, especially when you are traveling at highway speeds.
Uneven Tire Wear
A wheel bearing may seem small, but it can affect how the wheel is sitting against the road. If the bearing goes bad, it could contribute to tire wear that shortens the life of your tire or negatively impacts the handling of your vehicle. It is easy to mistake uneven tire wear for an alignment issue, especially if you experience any pulling to either side of the lane, so it is recommended to get your vehicle inspected.
ABS Warning Light
Your ABS warning light is for the Anti-lock Braking System. The dashboard light can be triggered by many things. Many modern vehicles have wheel speed sensors that are integrated into the hub assembly. When the wheel bearing goes bad, the excessive movement can interfere with the sensor readings and trigger the ABS warning light on the dashboard. If your ABS light comes on, it does not necessarily mean that your wheel bearing has gone bad, but it is definitely among the possible causes to look into.
Vehicle Pulling Slightly to One Side
Some drivers first notice it while cruising down I-10 when the vehicle starts drifting and requires constant steering correction. Alignment issues are the most common cause for your vehicle pulling to one side, but a severely worn wheel bearing could also affect the steering and cause it to pull. You might notice the vehicle slightly drifting to the side. There can be many different reasons for this, and an inspection is the best way to determine if it is a bad wheel bearing or something different like bad tires or your car needs an alignment.
Can You Drive With a Bad Wheel Bearing?
While many drivers can continue to drive for weeks or months after wheel bearing symptoms first appear, the problem will only get worse with time. The more miles put on a bad bearing, the higher chance for a costly repair.
Driving with a bad wheel bearing can cause a number of issues, including:
- Heat buildup
- Increased wear on the bearing
- Wheel hub damage
- Tire wear
- ABS sensor issues
How Long Can You Drive on a Bad Wheel Bearing?
How long you can continue to drive on a bad wheel bearing depends on several factors, including the severity of the existing damage, the vehicle weight, your driving habits, road conditions, Arizona temperatures, and the level of exposure to dust, water, or other road debris. Because of all these factors, some bearings may slowly deteriorate over months while others can fail quickly once you start to notice symptoms.
The safest approach is to repair the wheel bearing as soon as symptoms appear, rather than try to determine how much longer you can get by.
What Happens If a Wheel Bearing Fails Completely?
Let's say that life gets in the way, and you forget about the wheel bearing. Ignoring it for too long can cause it to completely fail. It is uncommon, but bearing failure can cause the hub assembly to move irregularly while driving, which can put you and your passengers at risk.
A bad wheel bearing that is on the brink of complete failure can cause significant wheel wobble. Once it has failed, it can cause damage to the hub assembly. The brakes will also wear down quicker, wheel speed sensors can get damaged, and in extreme cases, the steering can become unstable, there can be less vehicle control, and you could lose a wheel.
Before complete failure happens, the additional stress placed on the surrounding area and its components can also add significantly to the repair costs. By addressing the wheel bearing symptoms early, you can avoid larger repair costs.
Arizona Conditions That Accelerate Wheel Bearing Wear
Arizona has hot summers, and the triple-digit temperatures can place additional stress on wheel bearings and other suspension components.
Extreme Summer Heat
Wheel bearings were designed to handle heat, but prolonged exposure to extreme temperatures, like 100 days over 100 degrees, can cause the lubricant around them to break down and increase stress and friction on the components.
Potholes and Construction Zones
Phoenix is one of the fastest growing cities in the United States, so Arizona drivers encounter a lot of uneven roads, construction, road hazards, and other things that can cause sudden impact loads on the wheel bearings and suspension components. Repeated impacts, such as when you are traveling along the SR-51 every day and launching off the bridges, may accelerate wear and contribute to premature bearing failure.
Dust and Debris Exposure
Even though wheel bearings are sealed components, contaminants and debris can still enter the system and contribute to wear over time if the seals have become worn out. Arizona's dry desert climate has a large amount of dust, and our roads have a lot of debris from constant construction. Dust exposure can become even more significant during the monsoon season when dust storms are a weekly occurrence.
When Should You Schedule a Wheel Bearing Inspection?
While you are driving, if you notice any growling, humming, or grinding noises that seem to increase with the vehicle speed, you know it is time to schedule an inspection. The earlier you can get your vehicle seen, the easier it is to prevent damage.
The longer you wait, the worse the symptoms will become and it could turn a minor repair into a larger and costly repair.
Frequently Asked Questions
What are the first signs of a bad wheel bearing?
The earliest warning sign is usually a humming or growling noise that becomes more noticeable as vehicle speed increases.
Does wheel bearing noise get louder with speed?
In most cases, the wheel bearing noise will become progressively louder as the vehicle travels faster.
Can a bad wheel bearing cause vibration?
Yes. A bad wheel bearing can be felt through the steering wheel if left unattended.
Can a bad wheel bearing affect alignment?
A bad wheel bearing can lead to uneven tire wear, which can feel like an alignment issue.
How much does wheel bearing replacement cost?
Wheel bearing replacement costs vary based on the vehicle make and model, whether the bearing is integrated into the hub assembly, and whether additional components have been damaged. A professional inspection is the best way to determine the exact repair needed.