Driving with the Parking Brake Engaged: Risks and Damages Explained

Driving with the parking brake (PB) engaged for extended periods can have serious consequences on your vehicle's braking system. This practice can lead to overheating brake components, leading to potential damage to the rear brakes and other related parts. This article delves into the risks associated with using the parking brake continuously and the damage it can cause.

The Mechanics of Parking Brake Use

The parking brake, or emergency brake, is designed to hold the vehicle stationary when the ignition is turned off. It engages a set of brake shoes or pads in the drum or disc brake system, respectively. While it is fundamentally different from the regular braking system, many drivers mistakenly use the parking brake for extended braking, which can cause numerous issues.

Overheating the Rear Brakes

When a vehicle is driven for a significant period with the parking brake engaged, the brake shoes or pads are continuously applied. This overuse can cause the brake material to wear down rapidly and even melt. The result is an unsafe and inefficient braking system that can deteriorate the motor's performance and potentially cause a driving hazard.

Rear Drum Brakes

In the case of rear drum brakes, which are frequently engaged through the parking brake, the high heat generated can melt the brake pads. These pads are designed to slide between the brake drum and the shoes to slow down the vehicle. When the PB is engaged, the brake shoes are constantly in contact with the drum, creating excessive heat. This sustained heat can cause the brake drums to warp, reducing their efficiency and potentially leading to uneven braking and decreased stopping power.

Rear Disc Brakes

For vehicles equipped with rear disc brakes, the parking brake engages small brake pads within the brake rotor hat. When the parking brake is applied, these pads are continuously pressing against the rotor, causing rapid overheating. The combination of heat and constant pressure can warp the rotors, making them less effective and leading to premature wear. Warped rotors can also generate vibrations and uneven braking, significantly affecting the driving experience and safety.

Additional Damages to the Caliper

Extended use of the parking brake can also lead to damage to the calipers, another critical component in the braking system. The caliper is responsible for applying pressure to the brake pads, ensuring that the brakes function effectively. When the parking brake is engaged, the calipers are subjected to higher temperatures and continuous pressure, which can lead to several issues:

Increased Heat: The calipers, being metal, can become overheated, leading to potential warping or deformation.

Wear and Tear: Continuous application of pressure can cause premature wear on the caliper pins or pistons, reducing their effectiveness and increasing the risk of brake failure.

Brake Fluid Swelling: The heat generated by the constant pressure can cause brake fluid to expand, potentially leading to loss of hydraulic pressure and decreased stopping power.

Prevention and Recommendations

To avoid these risks and maintain the health of your vehicle's rear brakes, it is crucial to use the parking brake only as intended—when the engine is off and the vehicle is stationary. Here are some recommendations:

Avoid using the parking brake for extended braking. Instead, use the regular brakes for normal driving to distribute the heat and wear more evenly across the braking system.

Periodically inspect and replace brake pads, shoes, and rotors to ensure optimal performance and safety.

Ensure the parking brake lever is well-adjusted to prevent accidental engagement while driving.

Conclusion

Driving with the parking brake engaged for extended periods can have significant and often irreparable damage to your vehicle's rear brakes and related components. To minimize the risks and ensure safe and efficient braking performance, always use the parking brake as intended and avoid relying on it for regular braking. Regular maintenance and inspection of your braking system are key to maintaining your vehicle's safety and performance.