Final answer:
When driving downhill on a steep downgrade, shifting to a lower gear is crucial for controlling speed and ensuring safety.
Explanation:
When driving a large vehicle downhill on a very steep downgrade, it is essential to shift to a lower gear. This allows the engine to provide more resistance against the gravitational pull, aiding in controlling the speed of the vehicle.
Using a lower gear assists in engaging engine braking, which helps in maintaining a safe speed without solely relying on the brakes that can overheat or fail on long descents.
By shifting to a lower gear, you can better manage the speed of the vehicle and enhance overall safety on steep downgrades.
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