Practice question

What is the kingpin?

  1. Use only the trailer hand valve for normal stopping
  2. The vertical trailer pin that locks into the fifth wheel
  3. Skip the visual inspection if the vehicle moves during a tug test
  4. Drive at normal speed and correct problems after the trip

Answer: B — The vertical trailer pin that locks into the fifth wheel

The correct answer is shown above. Try the full quiz for additional practice.

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