Personal Injury Lawyer Atlanta, Georgia
Se Habla Español

When Tractor-Trailer Brakes Fail and Cause Serious Injuries

Truck repair service. Mechanic takes off a tractor-trailer's tire for brake replacement.

A significant portion of truck wrecks involve failure of the truck’s air brake systems.

According to a 2006 study by the Federal Motor Carrier Safety Administration, one of the most common vehicle-related causes of truck crashes was brake failure. Of the 967 truck crashes examined in the study, brake failure accounted for 29.4% of all truck crashes.

Large commercial trucks can weigh up to 25,000 lbs (five times more than the heaviest passenger car). When these massive vehicles collide with smaller passenger vehicles, they can easily cause severe injuries and fatalities.

We’ll examine how truck air brake systems work and how they can fail in critical situations. If you or a loved one suffered severe injuries in a large truck or tractor-trailer accident, contact our truck accident lawyers to discuss your case.

How Air Brake Systems Work

Car brakes only need a hydraulic fluid system to come to a smooth stop. Larger vehicles like semi-trucks, however, require air-powered (pneumatic) brakes in addition to a hydraulic system.

To feed the brakes, a compressor sits on the engine and takes in air to hold in the air reservoir.

When the driver presses the brake, the compressed air passes through a triple-valve system to the brake cylinder. Pressure forces the spring to compress and the brake mechanics to engage.

Unlike in a hydraulic system, if the pressure drops too low in an air brake system, the emergency brakes engage. So if the vehicle turns off or something goes wrong, the air brake system automatically stops the truck.

Air Brake Failure: Why Does It Happen?

Truck brake failure is often blamed for causing accidents. Many times, a truck driver who is trying to avoid liability for the crash will try to use the excuse that the truck simply failed to stop.

This sounds plausible at first glance. After all, large trucks weigh tons and can’t stop on a dime. But this reasoning assumes the brake system spontaneously failed at the worst possible moment.

In reality, improper maintenance by the trucking company or driver themself is most likely the culprit. We examine five reasons truck brakes might fail during the critical moments before a crash.

1. Improper Maintenance

Brake systems are designed so that catastrophic failure is a rare event. Brake failures usually happen due to performance problems caused by deficient maintenance.

Under normal circumstances, gradual braking allows the truck driver to slow or come to a stop without issue. The overall system makes up for any weaknesses present.

However, if the driver is forced to slam on the truck’s brakes, the deficiencies manifest. The brakes slow the truck, but not as fast as the driver expects, so it may feel like the brakes aren’t working at all.

2. Brake Imbalance

Performance issues may also arise from brake imbalance. In other words, some brakes may have degraded while others have not, or the brake system components are mismatched. Brake imbalance may lead to instability while braking or the brakes catching on fire.

There are two types of brake imbalance. Both can lead to loss-of-control crashes for air-braked trucks:

Torque Imbalance: If a truck has torque imbalance, some of the brakes will work harder and lock up quicker than others.

Pneumatic Imbalance: Pneumatic imbalance can result in a similar issue as torque imbalance, but the issue will primarily affect tires along a specific axle.

In either case, brake imbalance puts a truck at risk of jackknifing or trailer swingout. Both situations are highly dangerous and can lead to catastrophic collisions and property damage.

3. Overuse and Overheating Going Downhill

The trucker themself may be the cause of brake issues due to overuse.

Pressing the brakes for extended periods of time while traveling downhill can negatively impact the brake system’s effectiveness and durability. Known as “riding the brakes,” it’s a common habit among less experienced truck drivers.

Continuous overuse without proper repairs can lead to brake fade and performance issues. If there is severe deterioration, the brakes may overheat and catch fire.

4. Not Using the Front Brakes

Sometimes, in an effort to save money on brake maintenance and tire wear, a driver may disconnect the brakes on the tractor (the front end). The brakes on the trailer tires now bear the full burden of breaking for the entire rig. This weakens the truck’s ability to slow down and stop.

5. Overloaded Trailers

If a truck is carrying or hauling too much weight, it will require longer than normal braking distances to slow down. This can grind down even the best of breaks and is a serious public safety hazard. Overloaded trucks can place excessive stress on poorly maintained brake systems, leading to failure in a critical situation.

Investigating Truck Brake Failure After a Crash

Large trucks are designed to haul massive loads and stop as quickly and safely as possible to avoid disaster. When that doesn’t happen and people are injured or killed as a result, a swift investigation is needed to hold those at fault accountable.

Crash forensics can test the air brake system by checking the function of all valves, gauges, warning devices, and pressure supplies. A legal team can demand documents, records, and testimony regarding truck maintenance logs and the driver’s history.

Trucking companies may try to purge evidence in the weeks or months after a crash. Their lawyers will do everything they can to stall and protect the company and save the insurance company money.

Victims of a truck accident deserve full compensation for their pain and suffering. Discuss your case with a truck accident lawyer as soon as possible so they can begin investigating and preserving evidence.

Get the decisive and experienced truck accident experts after an air brake failure truck accident. Call Gary Martin Hays & Associates at (770) 934-8000.


Civil Justice
Avvo Rating 10.0 Superb
Nation's Premiere 2023
Client Champion Silver 2023
National Association of Distinguished Counsel
Expertise Best Workers Compensation Lawyers in Atlanta 2024
Expertise Best Wrongful Death Attorneys in Atlanta 2024
Expertise Best Car Accident Lawyers in Norcross 2022
Expertise Best Workers Compensation Lawyers in John's Creek 2022
Expertise Best Car Accident Lawyers in Conyers 2021
Expertise Best Car Accident Lawyers 2019
America's Top 100 Personal Injury Attorneys
Top 100 Trial Lawyers
Million Dollar Advocates Forum
MultiMillion Dollar Advocates Forum
Top 25 Motor Vehicle Trial Lawyers
Top 25 Brain Injury Trial Lawyers
Top 10 Trucking Trial Lawyers
Top 10 Nursing Home Trial Lawyers
Super Lawyers
Voted Best of Gwinnett 2020
Georgia Trial Lawyers Association
Avvo Clients' Choice
Avvo Clients Choice
10 Best Attorney 2023
Keenan Trial Institute
Better Business Bureau listing
Telly Awards