Brake lines are an essential part of any vehicle’s braking system. When the brake master cylinder generates hydraulic pressure, the brake lines transfer this hydraulic pressure to the wheel cylinders and calipers, ultimately enabling the braking action.
You can count on a steady and leak-free supply of brake fluid thanks to these lines, which are typically made of steel or reinforced rubber. However, brake lines can corrode, wear out, or become damaged over time, reducing the braking system’s effectiveness or causing complete brake failure.
Learn how to spot the common signs of a bad brake hose.
We will also explain the causes of brake line failure and what happens when you ignore the signs.
What Are Brake Lines?
Brakes are designed to keep you and your car safe on the road. In the case that your brakes fail, or are unreliable, you, your vehicle, and others on the road can be in serious trouble.
The brake lines play a key role in your vehicle’s overall brake performance and function, allowing your car to turn pedal pressure into stopping power. Most cars feature hydraulic brake systems, which use fluid to transfer the pressure applied by your foot to the brake. This is where your brake lines come into play.
The brake fluid is stored in the master cylinder and is transferred from the master cylinder to the brake calipers via the brake lines when the brake pedal is pushed. This pressure forces the calipers to clamp down on the brakes and, in turn, slow and stop the car.
How do brake lines work?
The brake lines connect you, the driver, to the brakes on your wheels. Designed to transfer pressure, these slim, tubes stand up to high temperatures, tension, and pressure. They shield the sensitive inner components of the braking system from dirt and humidity.
When you press the brake pedal, you activate a piston in the brake’s master cylinder. This pushes brake fluid, under high pressure, through the brake lines, all the way from the master cylinder to the brake calipers at your wheels.
Fluid transfer in brake lines
Brake lines are designed to handle high-pressure fluid transfers.
- When you apply force to your brake pedal, it causes the brake fluid in the master cylinder to pressurize. This pressurized fluid then travels through the brake lines, carrying your ‘stop’ command to the brakes at each wheel.
- Brake fluid cannot be compressed. That means it sends the force you put on the brake pedal almost instantly to the brake calipers, even though they are some distance away from the brake pedal.
Common Symptoms Of A Bad Brake Hose
Brake hoses are exposed to the elements like harsh temperature changes, humidity, and chemical compounds from the road. Over time, they’re going to deteriorate and exhibit bad brake hose symptoms that clue you into the need to perform a repair. Five common signs include:
- Leaks – If you see fluid dripping onto one of your rims or the ground and it’s clear or light brown, slightly oily to the touch, and odorless it’s probably a brake fluid leak and it could be coming from a brake hose.
- Spongy brakes – When the pedal feel isn’t firm and consistent when you press it but feels spongy, it indicates air has entered the system, which could be from a bad brake hose.
- Reduced braking power – Some vehicles have a dashboard warning that illuminates when the brake fluid is low, indicating ‘reduced braking power’. One common cause is a leak at a brake hose.
- Squealing or grinding brakes – When a brake hose has deteriorated and collapsed internally, it restricts flow back and forth to the brakes at that wheel. It can cause the brakes to drag, contributing to brake noises all the time, not just when the pedal is pressed.
- Uneven braking application – If a hose is leaking or has collapsed, the car could dive to one side when you apply the brakes or constantly feel like there’s an anchor on your car when you’re driving.
What Causes A Brake Hose To Fail?
A few different factors can contribute to a bad brake hose. The first and most common is that it can rupture from cracking or aging since rubber gets brittle and dry over time. Or, it can fail from rubbing through against a suspension component or some other type of physical damage.
Brake fluid contamination can also cause a faulty brake hose. If the wrong type of fluid is added, a hose can swell or degrade, causing it to collapse or spring a leak.
How Do I Fix A Brake Line Quickly?
We don’t want to recommend this as a method to fix a brake line quickly, but it is a temporary, short-term solution that can get you to the mechanic as long as that’s your only stop and it isn’t too far away. Attempt this at your own risk, and please drive carefully if you try it!
You’re going to need an adhesive, like tape or rubber cement, to patch the leak in the brake line.
- Rescue Tape is a very popular product a lot of DIY car repair fans keep in their glove box or trunk.
- Some drivers have also used duct tape or electrical tape, with mixed results.
- Most auto parts stores carry a special hydraulic system or brake system patching glue that can help.
Keep in mind: Be careful none of this gets into the brake line, as it can cause serious damage to other components.
Driving with leaky brake lines is very, very dangerous. The most important thing to remember here is that you need to get to the mechanic safely and immediately, and drive like someone’s great-great-grandparents are surfing on the hood. Drive slowly, brake gently, and don’t make any unnecessary stops along the way.