Leaking Brake Fluid From Caliper

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Leaking Brake Fluid from Caliper


Brake fluid is a critical component in the braking system of a vehicle. It transfers the force from the brake pedal to the brake calipers, allowing the vehicle to slow down and stop. However, sometimes brake fluid can leak from the caliper, leading to potential safety hazards and compromised braking performance. In this article, we will explore the causes of leaking brake fluid from the caliper and discuss the necessary steps to address this issue.

Causes of Leaking Brake Fluid from Caliper

1. Damaged Caliper Piston Seal

One of the most common causes of brake fluid leakage from the caliper is a damaged piston seal. The piston seal helps to create a tight seal between the piston and the caliper bore. Over time, the seal may wear out or become damaged, allowing brake fluid to escape.

2. Corroded Brake Lines

Corrosion can also contribute to brake fluid leakage from the caliper. If the brake lines leading to the caliper are corroded, they may develop small holes or cracks, causing brake fluid to leak out. It is important to regularly inspect the brake lines for signs of corrosion and address any issues promptly.

Signs of Leaking Brake Fluid from Caliper

It is crucial to be aware of the signs that indicate a leaking brake fluid from the caliper. Some common signs include:

  • Visible fluid drips or puddles near the caliper
  • Soft or spongy brake pedal
  • Brake warning light illuminated on the dashboard
  • Reduced braking performance

Steps to Address Leaking Brake Fluid from Caliper

1. Inspect the Caliper

Start by inspecting the caliper for any visible signs of leakage. Look for fluid drips or wet spots around the caliper area. If leakage is detected, proceed with further inspection and repair.

2. Replace the Caliper Piston Seal

If the caliper piston seal is found to be damaged, it must be replaced. This requires disassembling the caliper, removing the piston, and installing a new seal. It is recommended to consult a professional mechanic for this task to ensure proper installation.

3. Check and Replace Corroded Brake Lines

If corrosion is identified as the cause of the brake fluid leakage, the affected brake lines should be checked and replaced if necessary. This may involve cutting out the corroded section and installing a new brake line. Again, seeking professional assistance is advisable.

4. Bleed the Brake System

After any repairs or replacements, it is crucial to bleed the brake system to remove any air that may have entered during the process. Air bubbles in the brake lines can compromise braking performance and safety.


Leaking brake fluid from the caliper is a serious issue that requires immediate attention. It can compromise the effectiveness of the braking system and pose a risk to the driver and other road users. Regular maintenance and inspection of the brake system can help prevent such leaks, ensuring safe and reliable braking performance.