Are Your Brakes Locking Up? Here’s Why

There’s nothing more dangerous than driving on the freeway only to find out that your brakes aren’t working as they should.

What Does It Mean When the Brakes Are Locked Up?

If your brakes are locking up, it means that they’re unable to release their grip on the wheels. This occurs when the brakes’ friction material is stronger than the grip of the tires on the road.

Brake lockup can happen during a panic stop or when traversing over icy roads. In some cases, lightly stepping on the brake pedal is enough to cause the wheels to lock up.

Power brakes are more prone to locking up compared to manual ones. This is because power brakes require less effort to engage than the other.

What Happens to Your Vehicle When the Brakes Lock Up?

If the front brakes lock up, you might end up losing control of your vehicle and get into an accident. Locked brakes can also throw off tire balance and cause erratic handling.

Lastly, you might hear loud grinding noises and notice a burning smell accompanied by smoke.

What Causes Brakes to Lock Up?

There are a number of reasons why your brakes can lock up. Here are some of the most common ones.

Stuck/Bound Brake Caliper

When the brakes are applied, the caliper creates friction with the rotor to help the vehicle slow down.

Over time, brake dust can build up between the rotor and caliper, causing the latter to stick. Stuck calipers can also cause the brake pad and rotor to overheat, leading to premature wear.

Corrosion

A vehicle that’s been sitting in the garage for quite some time can have a bunch of rusty braking components, including the drums and rotors.

If you have a vehicle that hasn’t been driven for a while, you might want to inspect the braking system before pulling out of the driveway because it’s possible for the brakes to get locked up while parked.

Malfunctioning Antilock Braking System

Most modern vehicles have an antilock braking system (ABS) that prevents the wheels from locking up during sudden braking. This system helps the vehicle stop in a straight line and minimize the danger of skidding.

The ABS monitors the speed of each wheel to modulate brake pressure, control slippage, and maintain traction whenever the brakes are applied.

A typical ABS is composed of wheel speed sensors, an electronic control unit, a warning lamp, and a hydraulic modulator assembly.  Any one of these parts could fail for a number of reasons and trigger the ABS warning lamp.

Once the warning lamp pops up on your dash, it means that the system is no longer working, so you might want to have a professional mechanic inspect your vehicle right away.

Worn-Out Tires

Tires aren’t meant to last the lifespan of your vehicle. A normal set of tires can last anywhere between 60,000 to 75,000 miles, depending on driving conditions.

A tire with no visible faults doesn’t always mean that it’s perfectly fine. In some cases, an out-of-balance or out-of-round tire can lead to vibration that can be felt through the steering wheel.

Keep in mind that even though your tires are still capable of holding air, this doesn’t mean that they’re fine. A tire tread depth less than 2/32” calls for a replacement because it might not grip the road and it can cause the vehicle to skid under adverse weather conditions.

Overheated Braking System

Much like the engine, the braking system can only handle so much heat. Too much friction can cause the brake fluid to boil over and prevent other components from working altogether.

You might be dealing with a set of overheated brakes if you notice the brake pedal sinking lower than normal. You might also notice smoke coming from the brakes or a burning smell that’s strong enough to circulate in the cabin.

Lastly, overheated brakes can also produce squealing noises.

Wrong Brake Fluid

Brake fluid is forced through the brake lines and into the caliper pistons. The pistons then push the brake pads against the rotors, helping the vehicle slow down.

Similar to engine oil, your vehicle also requires a specific type of brake fluid. Using the wrong type or injecting contaminated brake fluid can cause the rubber components to swell and eventually lead to brake system failure.

Adverse Road Conditions

In some cases, your brakes can still lock up even after they’ve been serviced. This is usually because of adverse road conditions that are out of your control.

Rainwater or ice can cause the roads to get slippery, causing the tires to lose traction.

Seized Brake Caliper Piston

Corrosion, old brake fluid, and worn-out piston seals can cause the brake caliper pistons to seize and the brakes to lock up. In most cases, this usually happens to vehicles that haven’t been maintained for quite some time.

If your brakes haven’t locked up yet because of a seized piston, you might notice other symptoms like uneven brake pad wear and your vehicle pulling to one side when steering.

Faulty Brake Booster

A power brake booster helps reduce pedal effort while increasing pedal reserve. Brake boosters usually have a power reserve used to assist one hard stop.

The brake booster can fail and get stuck in boost mode, which means force is still being applied to the brakes even when you’re not stepping on the brake pedal.

What to Do When Your Brakes Lock Up

First things first一don’t panic. Be as calm as possible, turn on the hazard lights, and honk your horn to alert other drivers that you’re dealing with a serious problem.

If your vehicle has an ABS, keep your foot on the brake pedal. The pedal will vibrate or pulsate, which signifies that the system is working.

If you’re driving a vehicle that doesn’t have an ABS, it’s best to take your foot off the pedal and let the wheels gain traction. Then, try stepping on the pedal multiple times while manning the steering wheel. The brakes should eventually disengage.