CDL · CDL general knowledge
Which statement correctly describes downshifting when you face a long downgrade?
Correct answer: It lets the engine's compression and friction share the work of slowing down.
Answer options
- AIt is not recommended in vehicles with an automatic transmission.
- BIt lets the engine's compression and friction share the work of slowing down. Correct
- CThe best moment to do it is right after you start down the hill.
Why
Selecting a low gear before the descent lets engine compression and friction absorb much of the vehicle's energy, so the service brakes are used less and are less likely to fade. Shift down before you start downhill, and do this with an automatic transmission too.
About this question
Topic: CDL general knowledge License: CDL
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Where it applies: Asked in every state.
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This question is part of Mountain Grades and Brake Fade (16 questions). Take the full set and check your score.
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