CDL · Doubles and triples
Compared with an A-dolly, what is the main thing a B-dolly or C-dolly adds?
Correct answer: A second drawbar.
Answer options
- AA second air tank.
- BA second axle.
- CA second drawbar. Correct
Why
An A-dolly hooks to the trailer ahead with a single drawbar, while B-dollies and C-dollies use a double drawbar attached at two points, which gives a steadier connection.
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
- In the official CDL manual, the section on doubles and triples generally explains coupling and uncoupling for which combinations?
- What should you use to hold the second trailer still before you couple it to the rest of the doubles combination?
- When you drop the rear trailer from a double combination, what should you do with the air shut-off valve at the back of the front trailer?
- What is the reason for moving a dolly clear of the rear trailer before releasing it from the lead trailer?
- When you uncouple twin trailers, which of these is the final step?
- Which statement about converter dollies is accurate?
- You are getting ready to hook a second trailer to your rig. What can you use to hold that trailer in place?
- The dolly is now hitched behind the first trailer, and the second trailer sits on the dolly's fifth wheel. What is the proper way to test this coupling?
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