Operation & SafetyQuestion 51 of 60
On a vehicle with air brakes, when is the proper time to release the brakes during snub braking on a downgrade?
a.When your speed has been reduced to about 5 mph below your safe speed
b.Only when the vehicle comes to a complete stop
c.As soon as you touch the brake pedal
d.When the air pressure warning comes on
Explanation
During snub braking, you apply the brakes to slow the vehicle and then release them when you have slowed to about 5 mph below your safe speed. This lets the brakes cool between applications. Continuous light braking, by contrast, keeps heat building and can lead to fade.
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Related questions on this topic
- What is brake fade?
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- Compared to a car, how does the stopping distance of a heavy vehicle with air brakes change as weight and speed increase?
- If your air brakes fail and pressure drops, what safety feature will eventually stop the vehicle?
- What should you do first if the low air pressure warning comes on while driving?
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