CDL · Doubles and triples
You are about to hook up a second trailer that has no spring brakes. How can you hold it in place first?
Correct answer: Charge its air tank through the emergency line, then disconnect that line so the trailer's emergency brakes set.
Answer options
- ARelease its emergency brakes, then lower the landing gear and count on that alone to keep the trailer still
- BCharge its air tank through the emergency line, then disconnect that line so the trailer's emergency brakes set Correct
- CLeave it unsecured, since the weight of the converter dolly will be enough to keep the trailer from rolling away
Why
Charging the trailer's air tank through the emergency line and then disconnecting that line makes the trailer's emergency brakes come on and keep it from rolling. If you have doubts about those brakes, chock the wheels as well.
About this question
Topic: Doubles and triples License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
Practice the whole set
This question is part of Coupling Doubles and Converter Dollies (28 questions). Take the full set and check your score.
Practice Coupling Doubles and Converter DolliesMore questions from Coupling Doubles and Converter Dollies
- What must be done with the rear shut-off valves before air can reach the second trailer's air tanks?
- You are unhooking the second semitrailer of a double. To what point do you crank down its landing gear?
- What is unique about the way triple trailers are coupled?
- Which description best fits a converter dolly?
- You release the pintle hook before the converter dolly has been pulled out from under the second trailer. What is the likely result?
- When hooking a converter dolly to the second or third trailer, how can you tell that the trailer is at the right height?
- What are the basic components of a converter dolly?
- You are about to uncouple the rear trailer. What do you do first?
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