Engine braking
Letting the engine slow the vehicle through the gears, instead of making the brakes do everything.
When you lift off the accelerator while in gear, the engine resists being turned by the wheels and slows the vehicle. Selecting a lower gear increases that effect. It costs nothing, it does not fade, and it leaves the brakes cool for when you actually need them.
That matters most on long descents, which is where brakes overheat and lose effectiveness. The standard approach to a long hill is to pick the gear before you start down it rather than after, because changing down part way is harder once the speed has built.
It matters much more in a heavy vehicle than a car, which is why lorries and buses also carry retarders — an additional braking system designed for exactly this, so the service brakes stay in reserve.
11 practice questions on this
Each one shows the answer, and our note on why every other option is not it.
Car
- You're about to go down a steep hill. What should you do to control the speed of your vehicle? Safety margins
- When will you feel the effects of engine braking? Vehicle handling
- How can you use your vehicle's engine as a brake? Safety margins
- Why is it bad technique to coast when you're driving downhill? Vehicle handling
- What can result when you travel for long distances in neutral (known as coasting)? Safety margins
- Why is travelling in neutral for long distances (known as coasting) bad driving technique? Vehicle handling