Diagnosing and Repairing 7 Common Heavy-Duty Brake Issues

Safety should always come first in your operations, and no system within heavy-duty trucks is more crucial to safety than the brakes. Failure to keep on top of brake problems can lead to a range of hazards, endangering drivers, passengers, cargo, pedestrians, and other road users. The unfortunate reality is that brakes can be plagued with a range of problems that need to be addressed immediately. 

In this guide, you will learn about seven common heavy-duty brake issues and how to diagnose and resolve them. Armed with this knowledge, you can hit the road with peace of mind, knowing that your operations are carried out efficiently and safely.

The Importance of Maintenance

The best cure for brake issues is prevention. Routine maintenance keeps your breaks in peak condition, making component and/or system failure far less likely. This can help keep your vehicles on the road and not stuck in repair shop bays, costing you unnecessary time and money.

Fleet managers should invest in fleet maintenance software to keep on top of maintenance tasks and automate menial processes. Alternatively, both fleet managers and owner-operators can partner with a reliable heavy-duty brake repair shop. This way, you can benefit from a personal touch and build a relationship with professionals who understand your specific needs.

Common Issues, Diagnostics, and Repairs

Issue 1: Air Leakage in the System

Symptoms and Diagnosis

Recognizing a loss of braking pressure or hearing hissing sounds is a clear indicator of an air leak within your air brake systems.

Repairs

Addressing air leaks involves replacing the faulty components. By replacing these parts with high-quality alternatives and ensuring connections are tightly secured, we restore the system's integrity, improving both safety and brake responsiveness.

Issue 2: Faulty Brake Chamber

Symptoms and Diagnosis

Decreased brake force and uneven braking indicate a potentially faulty brake chamber, a critical component in converting air pressure into mechanical force.

Repairs

Replacing a brake chamber not only solves the immediate problem but also prevents future issues related to uneven wear or potential brake failure. This guarantees that braking force is evenly distributed across the vehicle, providing a safer and more reliable braking response.

Issue 3: Worn Brake Shoes and Drums

Symptoms and Diagnosis

Increased stopping distances and unusual noises during braking often signal that the brake shoes and drums are worn.

Repairs

Replacing these components is about more than just swapping old parts for new; it's about reinstating the system's ability to efficiently dissipate heat generated during braking. New brake shoes and properly surfaced drums enhance the vehicle's stopping power and prevent heat-related degradation of other brake system components.

Issue 4: Malfunctioning S-Cam and Pushrod

Symptoms and Diagnosis

If the brakes are dragging or there is uneven wear on the brake shoes, this could be a sign that the S-cam or pushrod is malfunctioning.

Repairs

Lubrication, adjustment, or replacement of the S-cam and pushrod not only fixes the immediate issue but also guarantees the longevity of the brake system. Properly functioning S-cams and pushrods ensure that the brake shoes are applied and released evenly, reducing the risk of premature wear.

Issue 5: Broken or Weakened Return Springs

Symptoms and Diagnosis

Continuous contact between the brake shoes and drum indicates failing return springs.

Repairs

Replacing weakened springs restores the system's ability to retract the brake shoes fully after application. This not only prevents unnecessary wear but also ensures the brakes are ready to deliver full force when next applied, maintaining optimal stopping power.

Issue 6: Frozen Brake Components

Symptoms and Diagnosis

Frozen components within the system can cause brakes to fail to apply or release, especially in cold weather.

Repairs

Addressing this issue involves removing moisture from the system and replacing components that are prone to trapping moisture. Installing moisture control measures, such as air dryers, can prevent water from entering the system and freezing, ensuring reliable brake operation in cold conditions.

Issue 7: Incorrect Air Pressure

Symptoms and Diagnosis

Incorrect air pressure levels can cause slow brake response times or an inability to maintain brake pressure.

Repairs

Correcting this issue entails adjusting the air pressure to the manufacturer's recommended levels and servicing the air compressor, if necessary. This ensures that the air brake system can generate and maintain the correct pressure, providing consistent braking performance.

When to Call For Professional Help

You should never gamble with your safety on the road. Neglecting any of the above-mentioned signs can lead to hazardous situations that, in some cases, can cause fatalities. If you recognize any of these symptoms in your truck, then seek out professional brake repairs immediately!

Final Thoughts

Although preventive maintenance measures should be put in place, brakes may still fail, and understanding the warning signs is essential. Owner-operators need to be aware of when their vehicle tells them that something is wrong with their brakes, while fleet managers should reinforce this within their drivers to guarantee safety on the road. Being aware of emergency protocols and where to call for heavy-duty brake repairs can help save time, money, and lives. 

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