CDL · Air brakes
Some trucks have a control in the cab for lowering air pressure to the front (steering axle) brakes. According to the CDL manual, when should you use it to cut that pressure?
Correct answer: Under no circumstances.
Answer options
- AWhenever you apply the trailer brakes fully.
- BUnder no circumstances. Correct
- CWhenever the road surface is slippery.
Why
Older trucks with this control could cut front brake pressure in half for slick roads, but doing so only reduces stopping power. Front-wheel braking works well in all conditions, even on ice, so the control should always stay in the normal position.
About this question
Topic: Air brakes License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
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This question is part of How Air Brakes Work (18 questions). Take the full set and check your score.
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