6.7 Cummins Exhaust Brake Problems

The 6.7 Cummins exhaust brake is a popular addition to many diesel-powered vehicles, providing improved performance and control when hauling heavy loads or going down steep grades. Unfortunately, it can be prone to developing problems that can affect its performance.

Common issues include air leaks in the exhaust system leading to poor braking power; faulty electrical connections that prevent the brake from engaging; failure of internal components such as the butterfly valve; and clogged intake filters which reduce airflow into the engine and thereby impairing brake activation.

In some cases, these issues can be resolved with relatively straightforward maintenance procedures like replacing worn parts or cleaning out dirt or debris from filter elements.

For some owners of the 6.7 Cummins diesel engine, exhaust brake problems can be a real issue. The exhaust brakes on these engines are designed to slow the vehicle down when descending hills or coming to a stop in order to preserve braking system components and reduce wear and tear on them.

Unfortunately, over time, these brakes can wear out or become clogged leading to poor performance and even complete failure of the system.

If you’re experiencing issues with your 6.7 Cummins exhaust brake system, it’s important that you have it inspected by a professional as soon as possible so that any necessary repairs can be made before further damage is done.

What Would Cause an Exhaust Brake to Stop Working?

An exhaust brake is designed to slow down a vehicle by using the back pressure created when the engine exhaust passes through the turbocharger. However, if an exhaust brake fails to work properly, it can cause major problems for drivers.

The most common causes of an exhaust brake not working are clogged or blocked air passages in the system, dirty or faulty air filters, aging and worn parts that need replacing, lack of lubrication on moving components and electrical issues including bad wiring connections or a defective control unit.

Additionally, some vehicles may require a software update in order for their brakes to function correctly. If you suspect your vehicle’s exhaust brake isn’t working as it should be then it’s best to take it into a mechanic straight away so they can diagnose any underlying faults before further damage occurs.

How Does the 6.7 Cummins Exhaust Brake Work?

The 6.7 Cummins exhaust brake is a device used to help slow and control the speed of an engine when going downhill. It works by using the backpressure created in the exhaust system to help reduce engine speed without having to use the brakes.

This helps preserve braking components, can increase fuel economy, and improve driver safety by providing better control over vehicle deceleration.

When engaged, it redirects exhaust flow through a butterfly valve which creates resistance that slows down the momentum of your vehicle while you’re driving downhill or on steep grades. As you slow down further and reach lower RPM levels, more air is diverted through this valve increasing back pressure even more so that your engine continues to slow down at a controlled pace until it reaches idle speeds – helping avoid excessive wear on other components such as brakes and drivetrain systems.

The Cummins 6.7L diesel engines are equipped with an Exhaust Brake feature which allows drivers to select between either “On” or “Off” settings based on their preference for increased safety while descending hills or slopes with heavy loads in tow.

What Controls the Exhaust Brake on a 6.7 Cummins?

The exhaust brake on a 6.7 Cummins is controlled by the engine’s electronic control module (ECM). This ECM is responsible for controlling all of the vehicle’s functions, including the exhaust brake. The ECM uses signals from sensors located in various parts of the engine to determine when to activate or deactivate the exhaust brake.

When these sensors detect that conditions are appropriate for braking, such as when descending steep grades or slowing down quickly, they will send an activation signal to the ECM and it will engage the exhaust brake accordingly.

Additionally, there may be manual override switches that can be engaged if desired; however, most vehicles have their brakes automatically managed by the ECM so this isn’t necessary.

Can Exhaust Brakes Damage Engine?

Exhaust brakes are an important safety feature for trucks and other vehicles, but they can also cause damage to your engine if not used properly. Exhaust brakes work by using the engine’s exhaust gases to create backpressure in the system, which slows down the vehicle as it descends a hill or steep grade.

In some cases, this can put too much strain on the engine components and lead to premature wear or failure of certain parts such as valves, pistons, rings and bearings.

This is especially true when using manual transmissions with low gear ratios that cannot adequately provide enough compression braking assistance. If you use your exhaust brakes often or in extreme situations (such as off-roading), make sure that you regularly inspect all of your vehicle’s components for signs of excessive wear or damage.

Additionally, always drive carefully when using exhaust brakes; never exceed safe speed limits while descending hills or steep grades.

6.7 Cummins Exhaust Brake Sensor

The 6.7 Cummins Exhaust Brake Sensor is an important component of the diesel engine that helps regulate exhaust back pressure and keep it in proper balance with the rest of the system. It monitors the amount of exhaust being expelled from the engine, allowing for a smooth transition when downshifting or traveling downhill.

The sensor also keeps your brake system running safely and efficiently by providing data to assist with braking performance and stability control systems. By monitoring exhaust back pressure, this critical component helps ensure optimal driving experience while keeping fuel economy at its peak level.

6.7 Cummins Exhaust Brake Sticking

It is not uncommon for the 6.7 Cummins exhaust brake to become stuck in one position, making it difficult to accelerate or decelerate smoothly. This issue can be caused by a variety of factors including worn parts, insufficient lubrication, and even contamination inside the valve body.

If you are experiencing this issue with your vehicle, it is best to take it into an authorized mechanic who can diagnose and repair the problem quickly and safely.

6.7 Cummins Exhaust Brake Works Intermittently

If you own a 6.7 Cummins Diesel Engine, you may have noticed that your exhaust brake is not working properly or intermittently. This can be caused by several factors such as a dirty air filter, faulty wiring, or worn out components in the braking system.

If these issues are not addressed quickly and correctly it could lead to more serious problems like engine damage or increased fuel consumption due to inefficient braking performance.

It’s important to get your vehicle inspected by a professional mechanic if you’re experiencing this issue with your 6.7 Cummins Exhaust Brake so they can diagnose and fix the problem before it becomes worse!

6.7 Cummins Exhaust Brake Stuck on

If your 6.7 Cummins exhaust brake is stuck on, it can be a serious issue that requires immediate attention. The exhaust brake helps reduce wear and tear on the brakes when driving downhill by redirecting some of the engine’s power to slow down the truck.

If this feature is stuck in the “on” position, you may find yourself unable to decelerate properly or even potentially lose control of your truck if you don’t react quickly enough.

To fix this issue, you should inspect for any mechanical issues with the exhaust brake system and make sure all components are connected securely as well as check for any electrical issues such as faulty wiring or sensors that might be causing it to remain activated.

It’s important not to wait too long before addressing this problem since it could potentially become a safety hazard while driving!


In conclusion, 6.7 Cummins Exhaust Brake Problems can be a major issue for owners of this truck model. If the problem persists it is worth taking your vehicle to a specialist mechanic as soon as possible to avoid any further damage or costly repairs in the future.

While it may not always be easy diagnosing and fixing the cause of exhaust brake problems, doing so can help you save money and keep your truck running smoothly over time.

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