A failing wheel bearing can quickly turn a smooth ride into a noisy, potentially dangerous situation. This article provides practical methods to diagnose issues with your ACDelco wheel bearings, offering insights beyond the common advice. It focuses on real-world experiences and less-obvious signs that indicate a problem is developing, allowing you to address it proactively and avoid costly repairs.
The most common symptom of a failing wheel bearing is noise. But it’s not always a straightforward roar. Many people immediately think of a constant grinding, but the sound can be more nuanced. It often starts as a subtle hum or clicking that changes with your vehicle’s speed.
Listening for Variations
**The key is to pay attention to when and how the noise changes.** Does it get louder when turning? Does it disappear when you apply the brakes lightly? These variations provide critical clues. For example, a noise that increases when turning often indicates the bearing on the *opposite* side is failing because that bearing is experiencing increased load.
The Road Test
Find a quiet stretch of road (safety first!). Drive at a moderate speed (30-40 mph) and gently swerve left and right. **Listen carefully for changes in the noise.** If the noise gets louder when you turn left, the right wheel bearing is likely the culprit, and vice-versa. This simple test can pinpoint the problem much faster than simply driving straight and waiting for the noise to become unbearable.
This test requires safely lifting your vehicle. Always use jack stands – never rely solely on a jack. Once the wheel is off the ground, grab it at the 12 and 6 o’clock positions and try to wiggle it.
Checking for Play
**A small amount of play is normal, but excessive movement indicates a worn bearing.** This is especially true if you hear a clunking sound while wiggling the wheel. Remember to compare the amount of play to the other side if you’re unsure what “excessive” feels like.
Beyond the Wiggle: The Spin Test
After the wiggle test, spin the wheel by hand. A healthy wheel bearing should spin smoothly and quietly. **If you feel any roughness, grinding, or hear unusual noises, it’s a strong indication of a failing bearing.** Sometimes, you might even feel a slight vibration in the suspension components while spinning the wheel. This is a telltale sign of internal bearing damage.
This method is more subjective but can be helpful in catching problems early, especially after a longer drive. After driving for at least 30 minutes, carefully (don’t burn yourself!) feel the hub area of each wheel.
Temperature Differences
**A significantly hotter hub compared to the others is a red flag.** A failing bearing generates excessive friction, leading to increased heat. While brakes can also cause heat, a faulty wheel bearing will typically result in a more localized and intense heat concentration at the hub. If you are not sure, drive for a while with no or minimal braking and repeat the test.
Interpreting the Heat
Consider ambient temperature and recent braking activity when interpreting the results. If it’s a hot day and you’ve been driving aggressively with frequent braking, some heat is normal. But a dramatic difference between sides, especially under normal driving conditions, warrants further investigation. A non-contact infrared thermometer can be helpful for a more precise reading.
In my experience as a mechanic for over 15 years, I’ve noticed a common misconception: people often delay replacing wheel bearings until the noise becomes unbearable. This can lead to more significant problems, including damage to the hub and spindle. I’ve seen instances where a neglected wheel bearing failure resulted in complete wheel separation – a terrifying and dangerous situation.
The Importance of Early Detection
**Early detection and replacement of a failing wheel bearing can save you money and prevent more serious safety issues.** One often overlooked aspect is the effect a failing bearing has on your ABS system. The wheel speed sensor relies on the bearing to provide accurate rotational data. A wobbly or damaged bearing can cause erratic readings, triggering false ABS activations or disabling the system altogether. This is particularly dangerous in emergency braking situations.
Choosing the Right ACDelco Wheel Bearing
Not all replacement bearings are created equal. While ACDelco is generally a reliable brand, there are different grades of bearings available. **I always recommend choosing a bearing that meets or exceeds the original equipment (OE) specifications.** This ensures proper fit, durability, and performance. Also, inspect the new bearing carefully before installation. Look for any signs of damage or contamination. A small amount of grease is normal, but excessive grease or debris indicates a potential problem. A quality bearing should spin smoothly right out of the box.
Beyond Replacement: Proper Installation
Even the best ACDelco wheel bearing will fail prematurely if it’s not installed correctly. **Proper torque is critical.** Using the correct torque wrench and following the manufacturer’s specifications is essential. Over-tightening can damage the bearing, while under-tightening can lead to premature wear and failure. Also, be sure to use new cotter pins and seals whenever replacing a wheel bearing. These small parts play a vital role in preventing contamination and ensuring proper bearing function. Often these items are included within an ACDelco wheel bearing kit.
My experience as a certified mechanic, combined with ongoing professional development, provides a solid foundation for the information presented in this article. I’ve personally performed hundreds of wheel bearing replacements and have seen firsthand the consequences of neglecting these vital components.
Understanding Wheel Bearing Function
According to Wikipedia, a wheel bearing is a set of steel balls or tapers held together by a metal ring, called a race. These bearings allow the wheel to rotate smoothly with minimal friction. As bearings wear, the friction increases, generating heat and noise. [https://en.wikipedia.org/wiki/Bearing]
ACDelco’s Reputation
ACDelco is a well-known brand for automotive parts, including wheel bearings. They are known for producing reliable and durable components. Choosing a trusted brand like ACDelco can help ensure a longer lifespan and better performance for your vehicle. Their website contains technical information on their products. [https://www.acdelco.com/]
This article offers three methods to identify a failing ACDelco wheel bearing. By combining listening tests, physical inspections, and heat checks, you can diagnose bearing problems early. Remember that prompt action can prevent more significant issues and maintain the safety of your vehicle.
How do I know if my wheel bearing is bad?
Common signs include a humming or grinding noise that increases with speed, vibration in the steering wheel, and looseness in the wheel when you try to wiggle it.
Can I drive with a bad wheel bearing?
It’s not recommended. A bad wheel bearing can cause the wheel to wobble, leading to loss of control, damage to other components, and even wheel separation.
How much does it cost to replace a wheel bearing?
The cost can vary depending on the vehicle make and model, labor rates, and the quality of the replacement bearing. Expect to pay anywhere from $200 to $600 per wheel.
Is it safe to replace a wheel bearing myself?
It can be, if you have the proper tools, experience, and knowledge. However, it’s a safety-critical repair, so if you’re not comfortable, it’s best to have a professional mechanic do it.
What causes wheel bearings to fail?
Common causes include wear and tear, contamination, improper installation, and impact damage.