How do I know if my rear wheel bearing is bad?

If your vehicle's rear wheel bearing is going bad, it's important to address the issue promptly to avoid further damage and ensure your safety on the road. Here's how you can identify a bad rear wheel bearing and take the necessary steps to fix it.

Signs of a Bad Rear Wheel Bearing

There are several common signs that may indicate a problem with your rear wheel bearing:

• Noise: A bad rear wheel bearing will often produce a loud, grinding or rumbling noise that increases in volume as you accelerate. The noise may also change in pitch as you turn the steering wheel.


• Vibration: A worn-out rear wheel bearing can cause a noticeable vibration in the steering wheel, seat, or floorboard, especially at higher speeds.


• Uneven Tire Wear: If one of your rear tires is wearing down faster than the others, it could be a sign of a bad wheel bearing.


• Looseness: Try gently rocking the tire back and forth. If you feel any play or looseness, it may indicate a problem with the wheel bearing.

If you notice any of these symptoms, it's important to have your vehicle inspected by a qualified mechanic as soon as possible.

Diagnosing a Bad Rear Wheel Bearing

To confirm a bad rear wheel bearing, a mechanic will typically perform a few tests:

• Inspect the wheel bearing for any signs of wear, such as pitting, cracking, or excessive play.


• Check the wheel bearing's temperature, as a bad bearing will often run hotter than a good one.


• Perform a road test to replicate the symptoms and pinpoint the source of the noise or vibration.li>
  

If the mechanic determines that the rear wheel bearing is indeed faulty, they will recommend replacing it to restore proper wheel function and ensure your vehicle's safety.

Replacing a Rear Wheel Bearing

Replacing a rear wheel bearing is a complex task that should be left to a professional mechanic. The process typically involves:

• Removing the wheel, brake components, and other related parts to access the bearing.


• Pressing out the old bearing and installing a new one.


• Reassembling the wheel assembly and ensuring proper alignment and lubrication.li>
  

Attempting to replace a rear wheel bearing yourself without the proper tools and expertise can be dangerous and may result in further damage to your vehicle. It's best to leave this repair to a qualified mechanic to ensure it's done correctly and safely.

What are the symptoms of a bad rear wheel bearing?

Squealing or Growling Sound
The typical sounds of worn-out wheel bearings are squealing and/or growling that intensify as vehicle speed increases.

How to tell if rear differential bearings are bad?

You can tell if rear differential bearings are bad by listening for unusual noises like whining, grinding, or howling, and feeling for vibrations or difficulty steering. Other signs include leaking oil, excessive tire wear, or overheating. A rumbling sound often points to a worn carrier bearing, while a whine during acceleration or deceleration can indicate a problem with the pinion bearing.
 
This video explains common symptoms of a bad differential and how to diagnose it: 1mVehicle FreakYouTube · Jan 19, 2024
Auditory symptoms

• Whining or whirring: A constant or intermittent whining, often heard at speeds above 20 mph, can indicate worn bearings. 
• Howling or rumbling: A howling or rumbling sound, especially at highway speeds, can point to worn carrier or pinion bearings. 
• Grinding: A grinding noise could be a sign of failing gears or bearings. 
• Clicking or clunking: This may occur during turns or sudden speed changes and can signal worn-out or damaged components. 

Other physical symptoms

• Vibrations: A noticeable vibration, especially when accelerating, can be caused by worn-out components. 
• Steering difficulties: The vehicle may pull to one side, or steering may feel sluggish, particularly during corners. 
• Oil leaks: A leaking differential is a sign of a seal failure, which can lead to insufficient lubrication and overheating. 
• Excessive tire wear: Worn-out differentials can cause uneven or excessive wear on the tires. 
• Overheating: A differential that consistently overheats during high-speed driving or heavy loads may indicate internal problems. 

This video demonstrates how to inspect a differential for signs of failure: 1mAuto Repair GuysYouTube · Sep 1, 2021

What is one of the first signs of bearing failure?

Early indications of bearing failure can include machinery that is running unevenly, or at an exceptionally loud volume, or with reduced accuracy. There are also some visual signs to look for. Here are 5 common signs of bearing failure: Abrasion - Generally caused by excessive wear and friction against mating hardware.

What can be mistaken for a bad wheel bearing?

A bad wheel bearing can be mistaken for issues with unbalanced tires, uneven tire wear, brake problems, and CV joint noise. These problems often have similar symptoms, such as grinding or humming noises and vibrations, which is why a thorough inspection is needed to correctly diagnose the issue.
 
This video explains how to differentiate between a bad wheel bearing and other potential issues: 59sBCA Bearings by NTNYouTube · Sep 27, 2023
Tires and alignment

• Unbalanced or unevenly worn tires: These can cause vibrations and noises that may seem like a bad bearing. A professional can distinguish between them. 
• Uneven tire wear: This can be a symptom of a bad wheel bearing, but it can also be caused by alignment issues or other suspension problems, which may be mistaken for a bad bearing. 

Brakes

• Brake noise: Noises like grinding or shaking, especially when braking, can be mistaken for a bad wheel bearing. However, brake noise typically occurs only when the brakes are applied, whereas a bad wheel bearing can be a constant noise.
• ABS sensor issues: A bent or damaged ABS tone wheel can sometimes rub against the sensor, creating a grinding or rubbing noise. 

Other suspension components

• CV joint (Constant Velocity joint): A bad CV joint can produce similar clicking, grinding, or vibration noises, particularly when turning. 
• Other suspension damage: Issues with ball joints, tie rods, or even a damaged strut can cause similar symptoms. 

This video demonstrates how to check for play in the wheel that could indicate a bad wheel bearing or ball joint: 59sWay of the WrenchYouTube · Aug 24, 2023
How to differentiate

• Test the noise: Gently swerving back and forth while driving can help isolate the sound. A bad wheel bearing noise will often get louder when turning in one direction and quieter when turning in the other. 
• Listen to the sound: A bad wheel bearing often makes a grinding or humming noise that increases with speed, while a CV joint will typically make a clicking sound when turning. 
• Inspect the wheel: Check for any wobbling or stiffness when lifting the car and manually spinning the wheel. A professional can perform a more thorough inspection to differentiate between a bad bearing and other issues.