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What Are Rear Wheel Bearings?


vehicle wheel bearing

Your vehicle has many components that rub together and create an incredible amount of friction. As you know, when there’s friction, there’s heat. Lubricants help reduce friction and cool components and extend their life. A bearing, be it wheel or any other is used to reduce friction. Without the wheel bearing in your car, the wheel would likely slide as opposed to roll. When wheel bearings begin to breakdown and fail to roll, drivers may notice significant differences as they drive. Get to know what the wheel bearing is, its purpose, and what the symptoms of a bad front or rear wheel bearing are.

What Is a Wheel Bearing?

Each wheel is equipped with a wheel bearing, a set of steel balls or rollers held by a cage in a ring of metal called a “race.” As the wheels spin, they create friction and heat. Wheel bearings help to reduce the friction, heat and protect the wheels and tires. The wheel bearing lies inside of the hub assembly. The hub is what holds the lug nuts that are used to secure the tires to the wheels. Hubs are made to support the weight of the vehicle, travel over all kinds of road conditions, turn corners while facilitating the wheels as they spin at many revolutions per minute.

Unbearable Bearings

After performing for thousands of miles, it is common for wheel bearings to wear out. The perpetual revolution of the wheels combined with the weight of the vehicle eventually leads to worn wheel bearings, making them unable to let the wheels roll effectively. In the past, wheel bearings could be repacked as they were more accessible. However, modern vehicles are equipped with sealed units to keep debris, dust, and moisture at bay. Sealed units last longer as they are able to prevent contamination and reduce premature wear. However, because they are one collective piece, they cannot be serviced, cleaned, or greased. Once the assembly is worn, the entire rear wheel or front wheel bearing requires replacement, often along with the hub, as well.

Signs of Worn Wheel Bearings

When wheel bearings lose their ability to roll, your wheels will generate more heat than usual and the ride may not be as comfortable. Where once the ride was smooth, you may detect shakiness and other disturbances. If your vehicle exhibits any of the symptoms below, your wheel bearings may need replacement:

  • Unusual Sounds – That rear wheel bearing noise you’re hearing isn’t your imagination. When wheel bearings aren’t able to roll the wheels and tires adequately, components will rub metal to metal. The friction produced from the rubbing produces a grinding sound that increases in volume with more speed.
  • Steering Wheel Shakes – Steering wheel shakes happen for a variety of reasons. Typically, when wheel bearings are the cause of such vibrations, you feel the shaking at lower speeds. The shaking will only get worse and may even occur while accelerating if not addressed.
  • Tire Damage – Poor wheel bearings can have a negative effect on your vehicle’s alignment. Poor alignment results in unevenly worn tires. Ideally, all four tires should be aligned with complete contact with the road, resulting in even wear. Worn tires can be dangerous, especially when driving in wet weather. Usually, the tire that is worn the most is often the same wheel that has defective bearings.
  • Vibrations and Shaky Ride – Failed wheel bearings produce an unfavorable ride. You’ll experience vibrations and tremors as you travel as a result of an increase in friction in the wheels causing them to change position. Until the wheel bearings are replaced, the shakiness will persist and may even worsen.
  • Play in the Wheels – Most often this symptom will be identified by a technician. When your vehicle is up on the lift, a technician will grab the wheel on either side and attempt to rock it back and forth. If the wheel assembly wobbles back and forth, worn out wear bearings are likely the cause.

Driving with a missing or faulty wheel bearing is hazardous. It is recommended that if your vehicle experiences any of the symptoms of a worn bearing, you have a trusted technician inspect the wheel assembly. If wheel bearings come loose or detach from the vehicle, it can create a very dangerous situation on the road. Wheel bearings play a vital role in keeping the wheel attached to your vehicle. Without wheel bearings, your wheel is essentially unattached. This can be very dangerous, especially while traveling on highways at high speeds. Losing a wheel could result in loss of control of your vehicle, putting yourself and other drivers in harm’s way.

If your vehicle exhibits any symptoms of failed or worn wheel bearings, don’t hesitate to bring your vehicle to your nearest Sun Devil Auto. Did you know that with each Sun Devil Auto oil change we include a complete multi-point inspection? As part of our inspection, our Technicians check front and rear wheel bearings for excessive play or movement. If any issue is identified within the wheel assembly, you’ll be alerted so that the issue can be repaired properly. We’re a family-owned and operated shop that has been in business for over forty years. Our commitment to providing quality auto care with experienced and certified technicians and top of the line equipment, at a competitive price is what makes our business the dealership alternative. Visit your neighborhood Sun Devil Auto today for all your automotive needs.