Is Engine Braking the Same as Gear Shifting?
2 Answers
Engine braking is not the same as gear shifting; you need to shift gears first to utilize engine braking. The details are as follows: 1. Introduction: Engine braking refers to lifting the accelerator pedal without depressing the clutch, utilizing the compression resistance, internal friction, and intake/exhaust resistance generated by the engine's compression stroke to create a braking effect on the drive wheels. 2. Principle: Engine braking means keeping the gear engaged without applying throttle, so the engine provides no traction to the vehicle. Instead, the rotation of the wheels drives the transmission system, and the idling engine generates a counteracting resistance on the vehicle. Higher gears result in less resistance from the engine, while lower gears produce greater resistance. This distinguishes it from clutch braking, service braking, and parking braking.
I used to frequently use engine braking on mountain roads, which is far more than just a gear-shifting operation. When going downhill, I would shift to a lower gear, release the throttle, and let the wheels drag the engine to create resistance, gradually slowing the vehicle. This is a physical braking technique that feels entirely different from pressing the brake pedal—it doesn’t wear out the brake pads and helps prevent brake overheating and failure. Many experienced drivers rely on this method to control speed on highways in regions like Yunnan, Guizhou, and Sichuan. Although the operation involves downshifting (e.g., from 4th to 3rd gear), the core principle is leveraging the compression resistance of the engine’s crankshaft and pistons to decelerate, similar to the concept of an air brake. Manual transmissions allow precise gear control to enhance the effect, while automatic transmissions can activate a similar function by shifting to S/L mode.
