The generic trademark name for a compression release engine brake, a Jake Brake is most commonly used in large diesel engines on semi-trucks.
How Does a Jake Brake Work?
Jake brakes are utilized by many truck drivers to control speed, especially on downhill slopes and highway exits where permitted. To activate a Jake Brake, the driver ceases to apply gas to the engine, engages the engine brake switch—typically integrated into modern manual gear shifts—and allows the vehicle to decelerate.
How Does An Engine Brake Work? A Simple Explanation of Jake Brake Mechanics
During regular operation of a large truck, air is drawn into the engine cylinders through the intake valve, where it undergoes compression to generate energy.
In engine braking scenarios, when the driver activates the engine brake switch, air once again enters the cylinders via the intake valve. However, this time, the Jake Brake directs the compressed air to the cylinders, instructing them not to transmit the energy to the wheels or the vehicle. Instead, the energy is expelled through the exhaust valves. This process produces a brief but loud noise and effectively slows down the vehicle without relying on traditional friction braking systems.
Other Names for Jake Brake:
- Jacobs Brake
- Jake Nett Braking
- Jake
- Compression Release Engine Brake
Examples of Jake Brake Used in a Sentence
“I need to preserve my brakes on this descent and let the Jake Brake handle most of the work as we coast down.”
“Hey, we’re in a truck stop parking lot, and that Jake Brake is pretty loud. Do you really need it on here?”
No Engine Brake Signs – “Trucks: Please No Jake Brake”
Some communities have banned the use of engine brakes due to their loud noise, which can disrupt local residents. Critics argue that the noise and vibrations from engine brakes can even damage nearby structures.
According to the Office of Legislative Research (OLR), several states and municipalities have enacted laws prohibiting the use of Jake Brakes, particularly near toll stations and residential areas. Exceptions may apply for emergency situations, and regulations vary by location, with some states requiring or permitting the use of brake retarders in specific circumstances.
