What is Parking Brake and How it Works?

What is parking brake?

It happened almost like ten years ago when I was newly learning how to drive. I went on a hiking tour with my dad in a nearby hillside area. My dad was driving for the whole time. As we reached our destination, we got off from the car by parking it beside the road.

After walking for a few minutes, I suddenly remembered that I had left my headphones in the backseat. I rushed to the car and got horrified to see what was happening!

Our car was not in the same position where we left it parked. Rather it was rolling down the road slowly! I hurriedly ran down to the car and checked the foot brakes. There was nothing wrong with them.

Only then I realized, my dad forgot to pull the parking brake! The parking brake provides extra stability to the car and prevents it from rolling away. After engaging it, the car stopped rolling and stood in a steady position.

This is how I got to learn the necessity of using a parking brake by a real-life experience. I wonder what would have happened back then if I had not left my headphones in the car!

However, you must be wondering what a parking brake actually is. Many of you have already heard about the emergency brake. The parking brake is as same as the emergency brake.

This brake is a completely mechanical system that bypasses the hydraulic braking systems to stop the car in an emergency or to keep it in place when parked.

Moreover, the parking brake is an extra support to the foot brakes when they fail to provide enough car lock system during parking your car in hilly tracks, slippery roads or even at the time of any kind of collision.

There is a myth regarding this parking or emergency brake famous in America. That is, you should ONLY use the parking brake during the emergency hours. Using it more often may make it useless in a while.

God, they are wrong! The name “parking brake” itself shows the reason for using it. Use it every time while parking your car whether your vehicle runs on manual or automatic transmission!

Is parking brake necessary?

I think my story above is suitable enough to tell you about the necessity of the parking brake.

In addition, if you drive a vehicle on the manual transmission or stick shifts, engage the parking brake every time while getting off the car. If you do not engage it, you might just find your vehicle rolling away all on its own.

On a different note, if your vehicle runs on the automatic transmission, setting the parking brake before you release the service brake pedal will keep weight off the transmission. Thus, it will make it easier for the vehicle to shift out of park.

You can add extra security in your vehicle with best rear view mirror dash cam which have parking mode for capturing videos while parking.

The manual transmission drivers can use the parking brake as a guide to forestall the rolling back of their car while parking on a slope. Pulling the brake while the car is parked, and later on letting it out can be tricky, so you should rehearse this move before using it on the road.

The parking brake saves you from unexpected accidents. If your vehicle is hit when parked, the parking brake will provide stability to the vehicle. Moreover, it will prevent the vehicle from rolling away.

If the emergency brake isn't used more often, the cables located under the car can corrode and get stuck in place. This will become a problem, as you may face difficulties to use the brake or the cable may be torn when you try to engage it.

How parking brake works?

Though it seems quite complicated, the process of how parking brakes work can be explained in simple terms. There is a device called “parking pawl” equipped in the automatic transmission vehicles.

The actual function of this device is to stop a car from rolling when it’s parked. In easy terms, the parking pawl is a metal pin that stops a car’s transmission from sending power to its output shaft while being engaged.

However, this relatively a small part of your vehicle, like every other part can easily be damaged or simply fail and cause brake failure of your car.

In the case of the manual transmission vehicles, when you pull the parking brake, the brake cable passes through an intermediate lever. This lever increases the power of your pull, and then passes through an equalizer.

The cable inside the U-shaped equalizer is split into two parts. The equalizer then sends the equally divided power evenly through the two cables connected to the rear wheels.

However, cars with rear disc brakes have comparatively a more complicated emergency brake system. Sometimes the system requires an entire drum brake system to be mounted inside of the rear rotor. It is called an exclusive parking brake or auxiliary drum brake system.

On the other hand, if the vehicle has rear disc brakes instead of an auxiliary drum brake, a caliper-actuated parking brake system is used. With this system, an extra lever and corkscrew are joined to the existing caliper piston.

When you engage the parking brake, the lever forces the corkscrew against the caliper piston, and pulls the brakes. As such it bypasses the hydraulic braking system once again.  

Nowadays you can find electric e-brakes available on some modern vehicles. This system does not engage any pedal, stick or center console lever but a small button on the dashboard. This button signals an electric motor to pull the brake cable.