Car Shaking Under Braking : Case Study & Solution

Car shaking under braking

Car Shaking Under Braking

Car shaking under braking can be a disconcerting experience for any driver. This phenomenon can range from mild vibrations to severe shaking that affects the vehicle’s control. Understanding the causes of car shaking when braking is crucial for maintaining vehicle safety and performance. This article delves into the various reasons behind this issue and offers insights into diagnosing and fixing the problem.

Why Does My Car Shake When I Brake?

Understanding why your car shakes when you brake can help you address potential safety concerns and maintain optimal vehicle performance. This section explores the specific reasons behind braking-induced vibrations and offers tips on how to resolve them.

  1. Warped Brake Rotors: Warped or unevenly worn brake rotors can cause the brake pads to grab inconsistently, leading to vibrations.
  2. Worn Brake Pads: Brake pads that are unevenly worn or have debris stuck to them can cause shaking during braking.
  3. Loose or Damaged Suspension Components: Components like tie rods, control arms, or wheel bearings can contribute to vibrations if they are loose or damaged.
  4. Tire Issues: Imbalanced or damaged tires can also lead to shaking when the brakes are applied.
Car Shaking Under Braking
Car Shaking Under Braking

Car Shaking in Idle

Experiencing car shaking while idling can be indicative of underlying mechanical issues. Unlike vibrations that occur while driving, idle shaking usually points to engine or fuel system problems. This section explores the possible reasons and remedies for a car that shakes when idling.

Potential Causes

  1. Engine Misfire: Misfires due to faulty spark plugs, ignition coils, or fuel injectors can cause the engine to shake.
  2. Vacuum Leaks: Leaks in the vacuum system can disrupt the air-fuel mixture, leading to rough idling.
  3. Motor Mounts: Worn or broken motor mounts can result in the engine vibrating more than usual.
  4. Dirty Fuel System: Clogged fuel injectors or dirty air filters can also contribute to rough idling.

Car Vibration at High Speed

Vibrations at high speed are not only annoying but can also signal more serious issues with your vehicle. These vibrations can arise from several sources, including the wheels, tires, and drivetrain. Identifying and addressing the cause is essential for safe and comfortable driving.

Car Vibration at High Speed
Car Vibration at High Speed

Common Causes

  1. Wheel Imbalance: Imbalanced wheels are a frequent cause of high-speed vibrations.
  2. Tire Issues: Problems like uneven tire wear, defects, or incorrect tire pressure can cause vibrations.
  3. Alignment Issues: Misaligned wheels can cause the vehicle to vibrate, especially at higher speeds.
  4. Drivetrain Problems: Issues with the driveshaft, axles, or CV joints can also lead to vibrations at speed.

Car Shaking While Driving

Car shaking while driving can affect the overall driving experience and may indicate a range of mechanical issues. Whether it’s a minor tremor or a severe shake, diagnosing the problem is crucial to avoid further damage and ensure vehicle safety.

Potential Causes

  1. Tire Problems: Worn, imbalanced, or improperly inflated tires are common culprits.
  2. Suspension Issues: Damaged or worn suspension components can lead to shaking.
  3. Brake Problems: Even when not braking, issues like sticking calipers can cause vibrations.
  4. Engine Issues: Misfires or other engine-related problems can manifest as shaking during driving.

Case Study: Car Shaking Under Braking in a Mercedes E-Class

In this case study, we explore a real-world situation involving a Mercedes E-Class owner who experienced car shaking under braking. The owner brought the car to a Mercedes dealership, where a qualified technician investigated and resolved the issue. This case highlights the diagnostic process and solution for brake-related vibrations.

car Shaking Under Braking in a Mercedes
car Shaking Under Braking

Background

The owner of a Mercedes E-Class reported a persistent issue where the car would shake noticeably when the brakes were applied. Concerned about the safety and performance of the vehicle, the owner decided to take the car to a certified Mercedes dealership for a thorough inspection.

Initial Inspection

Upon arrival at the dealership, the Mercedes technician conducted a comprehensive inspection, focusing on the most common causes of car shaking under braking:

  • Warped Brake Rotors
  • Worn Brake Pads
  • Loose or Damaged Suspension Components
  • Tire Issues
Car Shaking Under Braking
Car Shaking Under Braking

Diagnostic Process

  1. Visual Inspection and Basic Tests: The technician started with a visual inspection of the brake system, checking for obvious signs of wear or damage on the brake pads and rotors.
  2. Suspension and Tire Check: The suspension components and tires were also inspected to rule out any contributing factors. This included checking for tire imbalance, uneven wear, and suspension integrity.
  3. Brake Rotor Examination with Dial Indicator: Since the initial checks pointed towards potential rotor issues, the technician used a dial indicator to measure the run-out of the brake rotors. The Caliper and dial indicator revealed that the brake rotors were warped beyond acceptable limits.
Car shaking under braking
Car shaking under braking

Findings

The technician confirmed that the brake rotors were indeed warped. Warped rotors can cause uneven contact with the brake pads, leading to vibrations and shaking when the brakes are applied.

Car shaking under braking
Car shaking under braking

Solution

  1. Rotor Replacement: The technician replaced the warped brake rotors with new ones, ensuring that the new rotors met the manufacturer’s specifications.
  2. Brake Pad Check and Replacement: While replacing the rotors, the technician also checked the brake pads. Although they were not the primary cause of the issue, they were replaced to ensure optimal braking performance.
Front Brake Rotor MERCEDES-BENZ
Front Brake Rotor MERCEDES-BENZ

Road Test

After replacing the rotors and brake pads, the technician conducted a road test to confirm that the problem had been resolved. The car no longer exhibited shaking under braking, indicating that the warped rotors were the root cause of the issue.

Discussion with the Customer

During a post-repair discussion with the customer, the technician gathered more information about the circumstances leading up to the issue. The customer mentioned that the problem started after a recent visit to a car wash. The technician deduced that the hot brake rotors, resulting from extended driving, likely warped due to the rapid cooling effect of cold water from the car wash. This sudden temperature change can cause the metal to contract unevenly, leading to warping.

Can you replace brake rotors yourself?

Replacing brake rotors is a crucial aspect of vehicle maintenance that can significantly impact your car’s safety and performance. While many car owners rely on professional mechanics for this task, it’s entirely possible to replace brake rotors yourself with the right tools and knowledge. This guide will walk you through the process, offering insights into the necessary steps, tools, and safety precautions, empowering you to handle this essential repair confidently and efficiently.

Brake rotor replace steps

For brake rotor replace, follow the next steps looking at the attached image;

Can you replace brake rotors yourself?
Can you replace brake rotors yourself?

Step 1 : Remove, install

  1. Remove the brake caliper (1) with the brake pads from the front axle and secure it to the vehicle without straining the connected cables.
  2. Remove the brake caliper (1) with the brake caliper bracket from the front axle and secure it to the vehicle without straining the connected cables.
  3. Remove the brake caliper (1) with the brake caliper bracket from the rear axle and secure it to the vehicle without straining the connected lines.
  4. Remove the brake pads from the rear axle.
  5. Unscrew the locking screw (2) and remove the brake disc (3).

Step 2 : Clean

  • Clean the contact surface and the mounting seat of the brake disc (3).
  • Lightly grease the mounting seat of the brake disc (3).

Conclusion

This case study underscores the importance of a systematic diagnostic approach in identifying and resolving car shaking issues under braking. The Mercedes technician’s methodical inspection and use of a dial indicator were crucial in pinpointing the warped brake rotors as the cause. The resolution involved replacing the rotors and brake pads, restoring the vehicle’s braking performance. This incident also highlights the potential risks of exposing hot brake components to cold water, a valuable lesson for vehicle owners to consider.

By addressing the issue promptly and effectively, the dealership ensured the safety and satisfaction of the Mercedes E-Class owner, reinforcing the importance of professional maintenance and diagnostics in automotive care.