Why is coasting in neutral down a long grade considered dangerous in a vehicle with air brakes?

Pick an answer

1. It is dangerous only because it burns more fuel, not because of any loss of control on the way down the grade
2. It removes the engine's braking effect entirely, leaving only the service brakes to control a vehicle that can build up dangerous speed
3. Coasting in neutral automatically engages the parking brake as a safety measure
4. Neutral has no real effect on descent speed compared to staying in gear

Correct!

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