Bearings

WHAT IS A BEARING?

Bearings are a type of mechanical part used to support rotating shafts, wheels, gears, and more. Bearings are one of the most widely used parts because they reduce friction between moving parts and support and guide relative motion between components.

There are two main types of bearings:

1. Ball bearings are the most popular form of bearing used as wheel bearings and in wheel hubs. They are made to handle radial and thrust loads. They are built with an inner race, an outer race, rolling elements (the balls), and a cage.
2. Roller bearings feature rollers that make line contact. Line contact provides a higher load rating than point contact but a reduced spinning speed and increased friction. Tapered roller bearings and needle roller bearings are commonly used bearings in engines, transmissions, and differentials.

WHEEL BEARINGS & WHEEL HUB ASSEMBLIES

The most important bearings on your car, truck, or SUV are the wheel bearings. Located in the centre of the hub, wheel bearings reduce friction and usually come preassembled in a single unit, sometimes known as a wheel hub assembly, that allows the wheel to spin. To help wheel bearings last longer, they're tightly packed with wheel bearing grease in a waterproof housing.

How long do wheel bearings last?

Wheel bearings are engineered to last the life of your vehicle so you don't have to replace them. Most wheel bearings last 136,000 to 160,000 km, but your driving style and driving conditions such as potholes, rain, dust, and salt can reduce how long wheel bearings last. Wheel bearings need to be replaced as soon as they go bad.

How to tell if a wheel bearing is bad

There are many signs that can help you determine whether you have a bad wheel bearing. The symptoms of a bad wheel bearing are:

• Humming, whirring, rumbling, grinding, or clicking sounds
• Vibrations when you turn or accelerate
• Uneven tire wear
• Steering wheel play caused by a loose wheel assembly
• ABS or traction control malfunction or failure

OTHER TYPES OF BEARINGS

There are about a dozen bearings that serve different purposes in your vehicle, and all of them need to be maintained and sometimes replaced.

Depending on your vehicle's year, make, and model, it may be equipped with one of these types of bearings:

Axle shaft bearings allow the wheels to turn freely while supporting the weight of the vehicle and maintaining proper wheel alignment.

Driveshaft bearings, also know as centre support bearings or carrier bearings, connect different sections of the driveshaft and give the vehicle flexibility.

Some other types of bearings your car, truck, or SUV might have are distributor bearings, alternator and starter bearings, accessory drive bearings, and AC compressor bearings.

REPLACEMENT WHEEL BEARINGS

If you know you have a bad wheel bearing and are seeing one or more of the symptoms listed above, don't wait to replace it. At NAPA, we have wheel bearings that meet or exceed OEM part requirements.

If you're looking for a quality wheel bearing replacement, order online and pick up your parts at your nearest NAPA Auto Parts store or select home delivery.

If you're not sure how to tell when a wheel bearing is bad, visit a NAPA AUTOPRO service centre to have your car system inspected by one of our technicians.