How To Tell If Your Wheel Bearings Are Bad

By Gene Hannon Jr.


You Hear Noise While Driving
When a wheel bearing or hub assembly is bad, it will usually make a noise. The noise can vary when you turn, and also with speed. A grinding noise indicates that your wheel bearings are bad, and you should replace them. Common noises are squeaks, chirps, squeals, moans, grinding, growling, whining, humming, etc.
The Wheel Has Play
One good way to tell if a wheel bearing is bad is by taking hold of the wheel at 6 and 12 o'clock and attempting to shake it while the wheel is lifted off the ground. The amount of “wiggle” room that your wheel has is called play. There should be very little or no play in the wheel.
Is the wheel bearing bad? Checking for axial play
Check for axial play. Image courtesy of Mazda
If you do have play in your wheel, replace your wheel bearings or hub. If there is no play in your wheel, that doesn't necessarily mean your wheel bearing is good. Perform the following checks too.
Roughness or Noise When Turning the Wheel by Hand
When you rotate the wheel by hand and experience roughness or noise, this too can indicate bad wheel bearings.
The Hub is Hot
Another test is to check the temperature of the wheel hub after driving ten miles or so. The hub portion should be barely warm (the wheel itself will be hotter because of the brakes). The hub's job is to prevent friction with the body. If the hub is warm, friction is causing it to heat up, and you need new bearings. The bearings come with new races, replace these too when you replace the wheel bearings.
What Is a Wheel Bearing and Why Does It Fail?
Wheel bearings are usually ball bearings in a ring-shape with grease between the bearings. The wheel bearings bear the weight of the vehicle on the wheels and provide an even rolling surface for the wheels to turn smoothly. Wheel bearings are usually sealed for protection, but if the seal is broken, dirt and contaminants can enter and they will degrade the rolling surfaces, resulting in noise, roughness, heat, and extra play.
Packing a wheel bearing with grease
Packing a wheel bearing with grease. Image courtesy of Mazda.
Removing a wheel bearing from a Mazda pickup truck
Removing a wheel bearing. Image courtesy of Mazda.
For information on your vehicle, check out Chilton’s online database of repair information for detailed instructions, images, and specific tips from the vehicle manufacturer and our certified expert technicians. Keep your vehicle running smoothly with maintenance schedules, service and repair information, Technical Service Bulletins and Recalls at: http://www.ChiltonDIY.com and http://www.ChiltonPRO.com.
Chilton Editor, Gene Hannon, ASE Master Technician Gene Hannon Jr., ASE Master Technician lives in Maryland with his wife Paula; they have 3 girls, Jocelyn, Sarah and Carly. Gene began working with cars when he was 13 at his father’s (Gene Sr.) ESSO service center where he cleaned equipment and tools, scrubbed out the repair bays, and pumped gas. By age 16 he was turning wrenches and receiving technical training. He worked at the ESSO (later Exxon) station for 29 years. With his father and brother, the three opened Avalon Automotive, an 8-bay repair center, where he was a partner for more than 10 years. Gene joined the Chilton Team in 2006.

 

 

 

 


Posted 24 Jun 2013 12:04 PM by Gene Hannon Jr