What must a driver do before descending a hill?

Before descending a hill, it is crucial for a driver to gear down to maintain control and reduce speed. When driving downhill, the natural tendency of gravity will cause the vehicle to accelerate, which can make it difficult to control the speed if the driver does not adjust the gears accordingly. By shifting to a lower gear, the engine helps to slow the vehicle down, providing greater braking control and preventing the brakes from overheating due to excessive use. This practice is essential for maintaining safety while navigating downhill, especially with heavier vehicles that require more distance to stop.

Choosing to accelerate to maintain speed can lead to a loss of control when gravity pulls the vehicle down the slope, while using cruise control is inadvisable as it may not allow the driver to react appropriately to changes in terrain or traffic conditions. Keeping the same gear as used when going uphill may not be effective in controlling speed on a decline, as it does not utilize the engine's braking capabilities efficiently. Thus, gearing down is the best practice for safe vehicle operation during downhill descents.