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What is the function of the engine braking?

If you have never heard of the engine braking, the first step is to understand that this braking mode is common to all vehicles, and it cannot be activated with a pedal, button or lever, so don’t worry about looking for something like that.

In short, this brake is a safer way to drive the vehicle when it is on a very steep and/or long slope, such as downhill mountain slopes. Its function is to reduce the speed of the car, in the same way as the pedal brake, however, braking occurs without friction from the pads, delaying their wear and, more importantly, their heating. There are many cases of cars, especially trucks, that have no brakes when going downhill, as they end up having to reduce speed many times during the journey, so that the brakes overheat and stop working.

These episodes are more frequent than one might think, and the consequences can be disastrous. For this and other reasons, it is very important that drivers know how to use this function of their car correctly, so that they can travel more safely and obtain other benefits.

What is the engine brake and how to use it correctly

The engine brake has a very self-explanatory name. It is a way of braking the car by working with the engine’s revs, using gear reduction to reduce speed.

Have you ever been in a situation where, when you needed to reduce gear, you ended up reducing the speed a little too high for that gear? If this has ever happened to you, it was probably a slight “knock” forward, as if you had stepped on the brakes too hard. This is the action of the engine brake, reducing the speed of the car by downshifting. However, don’t worry, if used correctly, the engine brake will not produce any kind of jolt.

Basically, what happens is a sudden decrease in engine speed, causing the speed to be reduced as a consequence. However, you need to be careful, because the benefits of the engine brake are only worth it if it is used correctly, because using the engine brake incorrectly can damage the car’s gear system. Ideally, the reduction should be done gradually, that is, the gears should be reduced one by one according to the braking need, because the heavier the gear, the heavier the braking will be.

Therefore, the driver should be careful not to be at a high speed and reduce to a very heavy gear, such as second, for example. Furthermore, if the speed is very high and the engine speed is also high, it is necessary to reduce the speed slightly using the foot brake before using the engine brake.

Incorrect use, in addition to damaging the gearbox system, can also overheat the engine, causing irreversible damage to the system.

Myths about engine braking

Using it causes damage to the car engine

Many people believe that using this brake can force or damage important parts of the vehicle’s engine, but this statement does not correspond to reality. What actually happens is exactly the opposite. Using the engine brake causes the vehicle’s braking to be distributed between the engine and the pedal brake, which reduces friction with the asphalt and even preserves important parts of the car’s mechanics

Using the engine brake damages the gearbox

The correct use of this brake does not harm the gearbox in any way. What can occur is damage resulting from the incorrect use of this resource. To better understand, the engine brake must be used in a way that corresponds to the speed of the car, that is, being at a high speed and reducing to second gear will certainly cause damage to the gearbox. To use the engine brake, the gears must be reduced gradually, after the speed has been reduced using the pedal brake.

Increases the pressure in the crankcase, damaging the engine oil

When using the engine brake, what occurs is a considerable increase in pressure inside the engine itself, with the increase that occurs in the crankcase being much smaller than the first. Even if the pressure were the same, the system in question was designed to withstand pressures much higher than what this brake is capable of producing.

Overheats the engine

Just like with the gearbox, using the engine brake correctly does not overheat the engine. It is a fact that, with the reduction in engine speeds from changing gears, the engine tends to heat up, but it is a low level of heat that does not cause damage to the engine. Using this brake incorrectly, however, can lead to overheating of the engine.

Benefits of using the engine brake

The three main benefits of using the engine brake are related to fuel economy, safety and preservation of some components of the car.

Fuel economy

Many people may think that high revs will result in higher fuel consumption, but the opposite is true. Using the engine brake on downhill slopes, for example, causes the engine revs to rise without having to step on the accelerator, that is, without wasting fuel.

Safety

Using this brake gives the driver greater control over the car, mainly by keeping the speed low. In addition, it reduces the use of the pedal brake, also preventing it from overheating and leaving it in good condition for emergency situations.

Preservation

When the pedal brake is not applied, the brake pads do not wear out and the tires do not drag on the ground, they just roll, which also reduces their wear. Both situations occur when the engine brake is used, which reduces the use of the pedal brake and consequently the wear of the parts.

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