CDL · Air brakes
On a vehicle with air brakes, what do the brake shoes and linings press against each time you brake?
Correct answer: None of these are correct.
Answer options
- AThe S-cam
- BThe slack adjuster
- CNone of these are correct Correct
Why
Air pressure pushes out a rod that moves the slack adjuster and twists the S-cam, and the S-cam spreads the brake shoes apart. The shoes and linings then rub on the inner surface of the brake drum, creating the friction that slows the wheels; they do not press against the S-cam or the slack adjuster.
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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