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Doubles & Triples Practice Question 2

TDoubles & Triples · Question 2

A 'converter dolly' is:

• AA two-wheel cargo dolly
• BA small wheeled frame with a fifth wheel that converts a semi-trailer into a full trailer for use behind another trailer
• CA trailer brake
• DA repair tool

Correct answer: B. A small wheeled frame with a fifth wheel that converts a semi-trailer into a full trailer for use behind another trailer

Why: Converter dollies turn semi-trailers into full trailers for use as second or third units. They have their own brakes and require careful inspection.

How this question fits the Doubles/Triples test

Each additional articulation point multiplies rearward amplification. A driver pulling triples must steer earlier, brake sooner, and inspect twice as much equipment as a single-trailer driver.

Study technique for this topic

Learn the correct trailer placement order by weight, the procedure for converting a single to a double, and the special inspection items unique to converter dollies and pintle hook assemblies.

Related Doubles/Triples practice questions

• Q12. When braking a doubles or triples combination, you should:
• Q25. The total length of doubles or triples is regulated:
• Q38. The fifth wheel on a converter dolly:
• Q51. A 'lunette ring' is:
• Q5. The pintle hook is:

Continue your CDL preparation

The Doubles & Triples portion of the CDL knowledge exam covers more than this single question. Use this site's full Doubles & Triples bank to drill every topic, then test yourself with one of our state-specific practice sets to confirm you are ready for the actual DMV exam in your state. Always check your state's CDL handbook for any local addenda before the test day.

If you are still building your overall CDL foundation, start with the General Knowledge bank — every CDL applicant must pass it — and then work outward to the endorsements you plan to add.