About Exhaust Brake Switches

Heavy-duty utility trucks and over the road haulers rely on safety equipment to operate correctly under harsh conditions. Trucks without auxiliary braking can suffer brake damage and overheating during use under most heavy loads. The need to replace worn brake shoes and rotors can become an expensive maintenance issue for these work truck owners, but by adding an auxiliary braking system like an exhaust brake, the truck can manage heavy braking conditions longer and safer with the addition of the added braking power. Exhaust brakes utilize exhaust gas to decrease the combustion pressure created inside the engine, reducing speed with the power of the engine rather than the friction created in the brake equipment. They are activated by a switch controlled by the driver, that can connect directly to the brake valve relay or a computer controlled brake unit that varies the braking power produced by the brake.

Identification

An Exhaust brake switch can be identified by the exhaust brake valve housing that is found in the exhaust piping of the truck. The switch is located on the dashboard of the driver's seating array, and they operate the exhaust brake valves that are normally located within the engine compartment or under the passenger compartment. Exhaust brakes utilize a butterfly valve which closes or opens the passage of exhaust gas through the exhaust system. The exhaust brake switch will be placed inside the passenger compartment near the driver. Older models of exhaust brake use the switch to turn on the brake. All on or all off was the old fashioned exhaust brake. Today's modern exhaust brakes utilize a computer controlled switching unit which can vary the opening depending on the braking condition. The switch will be toggle type and when in the on position, the circuit is closed and the exhaust brake will operate.

History

Motor vehicle development is an industry that manifests the best operating equipment onto existing vehicle applications for better performance. In the case of aftermarket products for motor vehicles, the exhaust brake is one piece of equipment that was developed to aid in the braking ability of a truck and not the performance or speed. By using an exhaust brake switch to activate the braking power, a driver could customize the braking ability of the vehicle using the exhaust gases as and added boost to braking. Exhaust brakes could be found on long haul tractor trucks since the early 1930's since then the advancement and quality of auxiliary braking has been developed into the computer controlled braking power that can be purchased for personal or work trucks of all sizes.

function

The major component of an exhaust brake is a butterfly valve which constricts the space allowed for the exhaust gases to escape out the exhaust piping. The valve action is initiated by a brake switch controlled by the driver. By creating a back pressure in the exhaust system with the brake valve at a point of constriction, it limits the ability of an engine to produce combustion pressures inside the engine. This lack of compression causes the engine to operate at lower revolutions per minute using the engine as the source of added braking power. Slowing the RPM of a combustion engine slows the rate of acceleration, and reverses the increase of speed into a reduction of power and drive. Slowing a vehicle down using an exhaust brake is an effective way to reliably add braking power to a mechanical brake system.

Warning

Exhaust brakes are not designed to stop a vehicle completely. The exhaust brake will only reduce the RPM of the engine drive shaft which reduces speed and allows for better control of heavy loads during extreme braking conditions. Never rely on an exhaust brake to stop a truck in motion. The exhaust brake switch is the tool for slowing a heavy load to a manageable speed with an exhaust brake completing the braking procedure using the mechanical braking system the vehicle is equipped with. The use of mechanical brake pads and shoes as the way a truck slows a heavy load cause extreme heat and wear to braking systems that can wear down during use. By using an exhaust brake to supplement the braking ability of the vehicle, the existing brake equipment will be able to last longer and operate better with the addition of auxiliary exhaust braking. Large or small, if your truck hauls or pulls a heavy load, consider adding an exhaust brake to help you stop.

Considerations

If you own a truck that pulls or hauls a heavy load, then an exhaust brake might save on brake maintenance costs dramatically. Using the right switch to supply the exhaust brake with power to operate can be done with different types of switches. A Toggle switch complete a circuit completely and creates and on off situation for operation. A variable switch will close the valve depending on the amount the power is applied creating a variable braking ability. To use a Toggle switch to turn on a mechanical brake controller will initiate the operation of a number of switches which run during the brake's use.

Expert Insight

Gale Banks is a man who understands truck power and diesel performance. Having built the fastest diesel vehicles in the world, the Gale Banks organization custom builds truck equipment like exhaust brakes and braking controllers. The development of exhaust brakes for truck use has been one of the most successful departments of the Gale Banks product line and his equipment has been tested and recommended for use by truck owners from around the world. His high-flow exhaust brakes have been in use longer, and come with a complete warranty and technical support from the Gale Banks operation in Azusa California.

Resources

• Exhaust Brake Description