Car Shakes When Braking

Experiencing a car shake when braking? Don't panic! This guide will help you troubleshoot the issue and get your car back on the road smoothly.

Experiencing unsettling shaking throughout the entire car while applying the brakes can be a concerning issue for any driver. In such cases, it is essential to identify the root cause promptly and seek appropriate solutions to ensure both safety and a smooth driving experience. One common culprit behind this disconcerting phenomenon is the misalignment between the rear brake shoes and drums. This article will delve into the reasons behind this misalignment and discuss the necessary steps to rectify the problem.

Understanding the Reason of Car Shake When Braking Issue

When the entire car shakes during braking, it often signifies that the rear brake shoes and drums are not making even contact. This misalignment leads to irregular braking and causes vibrations throughout the car. The primary cause of such misalignment can usually be attributed to warped rear drums. However, there is also a possibility that the drums are in good condition, but the rear wheel bearings have become worn or loose, indirectly causing the misalignment between the shoes and drums.

The misalignment between the rear brake shoes and drums, which causes the entire vehicle to vibrate while braking, can be attributed to a few different reasons. Let's explore the primary causes behind this issue:

1. Warped Rear Brake Drums

One of the most common reasons for misalignment is warped rear brake drums. During braking, immense heat is generated in the braking system, particularly in the drums. Over time, this heat can cause the metal in the drums to warp, creating an uneven surface. As a result, the brake shoes do not make uniform contact with the drums, leading to vibrations.

Warped rear brake drums can cause issues with braking performance and overall vehicle safety. Here's how you can determine if your car's rear brake drums are warped:

1.1. Brake Pedal Vibration

One of the most common signs of warped brake drums is a pulsating or vibrating brake pedal when you apply the brakes. This usually occurs when you're slowing down or coming to a stop.

1.2. Uneven Braking

If you notice that your vehicle pulls to one side when you apply the brakes, it could be an indication of uneven braking caused by warped rear brake drums. This can happen because the braking force is not being distributed evenly across the drums.

1.3. Squealing or Squeaking

Warped brake drums might produce unusual squealing or squeaking noises when you apply the brakes. This could be due to the uneven contact between the brake shoes and the drum surface.

1.4. Increased Brake Wear

If the rear brake drums are warped, they might cause uneven wear on the brake shoes. Inspect the brake shoes for signs of uneven wear or excessive heat, as this can indicate a problem with the brake drums.

1.5. Hot Brake Drums

After driving, you can carefully touch the rear brake drums (if they're accessible) to check for excessive heat. If the drums are much hotter than usual, it might be a sign that they are not dissipating heat properly due to warping.

1.6. Visual Inspection

If you can safely remove the wheel and visually inspect the rear brake drums, look for any signs of irregularities. Warped drums might have grooves, ridges, or uneven wear patterns on their surfaces.

1.7. Professional Inspection

If you're unsure about the condition of your rear brake drums, it's always best to have a professional mechanic inspect your vehicle. They can perform a thorough inspection, measure the runout of the brake drums, and determine whether they need to be resurfaced or replaced.

Remember that braking issues can significantly impact your vehicle's safety. If you suspect that your rear brake drums are warped or if you're experiencing any of the symptoms mentioned above, it's crucial to address the issue promptly to ensure your safety and the safety of others on the road.

2. Worn or Loose Rear Wheel Bearings

The rear wheel bearings play a crucial role in maintaining proper alignment between the brake shoes and drums. If the wheel bearings become worn or loose, they can allow excessive play in the wheel assembly. This play can cause the brake shoes to shift or tilt during braking, leading to uneven contact with the drums and resulting in vibrations.

Worn or loose rear wheel bearings can lead to various issues, including abnormal tire wear, noise, and handling problems. Here's how you can determine if your car's rear wheel bearings are worn or loose:

2.1. Abnormal Noise

One of the most common signs of worn or loose rear wheel bearings is a humming, growling, or rumbling noise that increases with vehicle speed. The noise might be more noticeable when turning in one direction versus the other.

2.2. Vibration

If you feel a vibration in the steering wheel or the seat, it could be due to worn or loose rear wheel bearings. The vibration might be more pronounced at higher speeds.

2.3. Uneven Tire Wear

Worn rear wheel bearings can cause uneven tire wear, typically on the inner or outer edges of the tires. If you notice unusual wear patterns, especially on one side of the vehicle, it could be a sign of bearing problems.

2.4. Looseness or Play

If you lift the rear of the vehicle and grip the top and bottom of the tire, you can try to rock it back and forth. If you feel any play or looseness in the wheel, the wheel bearings might be worn or loose.

2.5. Handling Issues

Worn or loose rear wheel bearings can affect the vehicle's handling, causing it to feel less stable or responsive. If you notice changes in how the car handles, especially at higher speeds or while making turns, it could be due to wheel bearing problems.

2.6. Heat

After driving, carefully touch the rear hub area (the center of the wheel) to check for excessive heat. If the hub is significantly hotter than the surrounding components, it might indicate that the wheel bearings are generating excessive friction due to wear.

2.7. Professional Inspection

If you suspect worn or loose rear wheel bearings, it's recommended to have a professional mechanic inspect your vehicle. They can lift the car, check for play in the wheels, and conduct a thorough inspection to determine the condition of the wheel bearings.

It's important to address worn or loose rear wheel bearings promptly, as they can impact your vehicle's safety and handling. If you're experiencing any of the symptoms mentioned above, or if you're unsure about the condition of your rear wheel bearings, it's best to have a professional mechanic diagnose and address the issue.

3. Improper Brake Adjustment

In some cases, the misalignment may be due to improper brake adjustment. If the brakes are not adjusted correctly, it can lead to uneven contact between the brake shoes and drums, causing vibrations during braking.

4. Debris or Contamination

Accumulation of debris or contamination between the brake shoes and drums can also disrupt the even contact necessary for smooth braking. Dust, dirt, and rust particles can interfere with the braking surface, leading to misalignment and vibrations.

5. Defective Brake Components

Faulty or defective brake components, such as misaligned brake shoe hardware, can contribute to misalignment issues. If the brake shoe hardware, like springs and clips, is not properly aligned or installed, it can affect the way the brake shoes interact with the drums.

Resolving the misalignment issue involves a comprehensive inspection of the braking system by a qualified mechanic. Once the specific cause is identified, appropriate measures can be taken to rectify the problem. This may include:

• Machining or resurfacing the rear brake drums to eliminate warping

• Replacing worn or loose rear wheel bearings to ensure proper alignment.

• Adjust the brakes correctly to achieve even contact between the brake shoes and drums.

• Cleaning the braking components thoroughly to remove debris or contamination.

• Ensuring all brake components are in good condition and properly installed.

Regular maintenance and timely inspections of the braking system can help prevent misalignment issues and ensure the safety and optimal performance of the vehicle's brakes.

Addressing the Car Shaking While Braking Issue

To resolve this issue effectively, it is crucial to take the car to a reputable garage or service center, with AAA garages being recommended for their trusted expertise. A qualified mechanic should inspect the rear wheel bearings to check for any signs of wear or looseness. If the bearings are found to be in good condition, the focus should then shift toward correcting the warpage in the rear brake drums.

1. Inspection of Rear Wheel Bearings.

Proper diagnosis begins with a thorough examination of the rear wheel bearings. The mechanic will meticulously assess the bearings' condition, ensuring they are functioning correctly and securely attached. If any issues are detected, the bearings should be replaced promptly to prevent further complications.

Rear Wheel Bearing

2. Machining the Rear Brake Drums

Once the rear wheel bearings are deemed to be in satisfactory condition, the mechanic will proceed to machine the rear brake drums. This process involves the careful removal of any imperfections or warpage on the drum's surface. By restoring the drums to their proper shape, the even contact between the brake shoes and drums can be re-established.

Rear Brake Drums

3. Replacing Rear Brake Shoes.

After the rear drums have been corrected, there may be an issue with the old brake shoes aligning well with the newly machined drums. To ensure optimal braking performance and safety, it is advisable to replace the rear brake shoes with new ones that can effectively mate with the recently machined drums.

Drum Brake assembly

4: Rear Brake Shoe

Conclusion

Experiencing car-wide shaking while applying the brakes can be an unsettling and potentially dangerous issue for drivers. When this occurs, the misalignment between the rear brake shoes and drums is often the culprit behind the problem. Whether caused by warped rear drums or worn/loose rear wheel bearings, it is essential to address this issue promptly.

Seeking the expertise of reputable mechanics and garages, like those affiliated with AAA, can ensure a thorough inspection and proper resolution of the problem. By machining the rear brake drums and replacing the rear brake shoes, drivers can regain a smooth and safe braking experience, restoring confidence on the road. Regular brake system maintenance and timely repairs remain paramount for all car owners, contributing to safer and more enjoyable journeys.