To which gear should you shift when driving downhill to assist in speed control?

Shifting to low gear when driving downhill is essential for controlling your speed and maintaining safe vehicle handling. When in low gear, the engine's power is more effectively utilized to slow the vehicle down naturally through engine braking. This helps prevent the brakes from overheating and reduces the risk of brake failure due to excessive use. Engine braking occurs when the throttle is closed, and the vehicle's momentum turns the engine, creating a resistance that slows down the car.

Using neutral gear is inappropriate for downhill driving as it disengages the engine from the wheels, eliminating engine braking and increasing the risks of losing vehicle control. High gear is suited for higher speeds and would not provide enough braking force on a downhill slope, leading to an increase in speed rather than a controlled descent. Overdrive is designed for fuel efficiency at high speeds and is not suitable for managing descent on hills since it allows the vehicle to coast, further compromising speed control. Thus, using low gear is the best practice for safe and effective speed management while going downhill.