Rick's Free Auto Repair Advice

How to diagnose a bad wheel bearing

Learn the most accurate way to diagnose a bad wheel bearing

You’ll see many of the techniques on the Internet for how to diagnose a bad wheel bearing, like rocking the wheel at 9:00 and 3:00 and 12:00 and 6:00, driving on a flat road and listening for noise change by moving the steering wheel slightly. Some of those techniques work. But they often result in replacing the wrong bearing. That’s because the vibrations can travel and make you think it’s the left side when it’s really the right. Let’s go over the most common techniques and then I’ll show you the one technique that nails it and always find the right bearing.

Check for wheel bearing play

I’m suggesting you check for wheel bearing play, but I have to point out that a wheel bearing has to be pretty darn worn to have detectable play just by using your hands. Sure, you can try this method, but if you don’t feel play using your hands, that doesn’t mean the bearing isn’t worn. To conduct an accurate test for wheel bearing play, you really need to use a dial indicator.

• Jack up your vehicle and support it with jack stands.
• Grasp each wheel at the 12:00 and 6:00 o’clock position and rock it while checking for movement.
• Grasp each wheel 3:00 and 9:00 o’clock position and rock it while checking for movement.

There should be no movement. If you detect movement, replace the wheel bearing.

Listening for the sounds of a bad wheel bearing

Snapping, Clicking or Popping

Normally heard when making sharp turns. This type of noise can indicate excessive bearing end play from inadequate clamping (improper axle nut torque). It can also indicate a worn or damaged outer CV-joint.

Grinding When the Vehicle is in Motion

The grinding noise is normally heard when turning or when there is a shift in the load. It’s caused by a loss of integrity such as roller or raceway damage. It typically suggests mechanical damage in a wheel-end system.

Knocking or Clunking

This noise is normally heard when shifting – either when changing directions or  transitioning from accelerating to coasting. This noise can signal excessive play in the CV-joints or U-joints or excessive backlash in the differential gears, a condition not generally associated with bearings.

Humming, Rumbling or Growling

These noises normally associate with tire, electrical or drivetrain components. If bearing-related, the noise or vibration presents when driving in a straight line, but intensifies when slightly turning the steering wheel. Typically, the side opposite the rumbling is the defective side.

• Wheel bearing noise may be rhythmic
• May change tone as you shift body weight left and right and accelerate/decelerate.
• If the noise lessens when you sway right, then the worn bearing is probably on the left wheel bearing. If it lessens when you sway left, a right wheel bearing is likely worn.

Take a test drive and listen for wheel bearing noise

• Cyclical wheel bearing growling or humming noise typically becomes louder at faster speeds.
• The noise may get louder or quieter or even disappear as you move the steering wheel, change lanes, or make a turn. This happens because the vehicle weight transfers as you make these maneuvers.
• On 4WD pickups, you may notice that you have to add more steering effort to corner or maintain the vehicle on a long sweeping curve. That can be a sign of a worn wheel bearing even if it isn’t making noise.

You’ll have to maneuver left and right while changing vehicle speed. So locate a flat level road that extends for several miles. Drive the vehicle at various speed with acceleration and deceleration. During each acceleration and deceleration, turn the wheel SLIGHTLY from the 10:00 o’clock to 2:00 o’clock position. Do NOT turn the wheel to extremes beyond those positions. Most wheel bearing noises will show up between 10:00 and 2:00. Keep in mind that all you’re trying to do with this test is shift vehicle weight forward and backward and left to right.

The killer method to locate a bad wheel bearing: This one never fails

Use an electronic stethoscope to diagnose a bad wheel bearing

Here’s a fail-safe way to find the bad bearing. Use an electronic stethoscope. The kit comes with microphones you to each wheel and then take if for a drive. While driving, you switch to each microphone until you find the one with the noise. This always works and buying the tool costs less that replacing the wrong bearing.

Steelman Chassis Ear is the tool to use. It’s available in two styles: wired and wireless. The wired kit requires you to route the wires back into the passenger compartment while the wireless units transmit the sounds without running cables.

So here’s my advice: Buy a kit new or used. Use it to locate the bad bearing. Then sell the kit on ebay. Yeah, you’ll lose about $50, but you’ll wind up replacing the right bearing, which will save you even more money.

wheel bearing noise

Steelman Chassis Ear wired version

 

wheel bearing noise

Steelman Chassis ear wireless version

Causes of Bad Wheel Bearings

• Improper Installation: Improper torque when installing a new bearing the #1 cause of rapid failure.

• Unbalanced Tires: Unbalanced tires strain the bearings.
• Overweight Loads: Excessive weight damages bearings.
• Harsh Road Conditions: Rough roads and potholes take a toll on bearings.

Can You Drive with Bad Wheel Bearings?

While it’s possible to drive temporarily with a bad bearing, it’s not recommended. Continuing to drive can lead to more severe damage and compromise safety.

©, 2018 Rick Muscoplat

 

Posted on by Rick Muscoplat

Categories




Custom Wordpress Website created by Wizzy Wig Web Design, Minneapolis MN