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Doubles & Triples Practice Question 22

TDoubles & Triples · Question 22

A common cause of separation between a tractor and trailing unit is:

  • AFailed kingpin
  • BImproperly latched fifth wheel or pintle hook on the dolly
  • CWorn tires
  • DABS failure

Correct answer: B. Improperly latched fifth wheel or pintle hook on the dolly

Why: Improperly engaged or worn coupling devices are the leading cause of trailer separation. Visual inspection plus tug test prevents most separations.

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.

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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.