- A Close around the kingpin head only
- B Be removed
- C Stay open
- D Close completely around the kingpin shank Correct answer
Why this is the correct answer
The jaws close around the cylindrical shank of the kingpin, not the head. A high hitch (jaws closed around the head) can release in transit.
How this topic appears on the test
The Combination Vehicles CDL exam covers Coupling as a recurring theme. Test-writers favor questions that probe whether the applicant has internalized the safe operating procedure, not merely memorized the rule. When you encounter a question on this topic, slow down and verify that the answer you've chosen describes what a careful, defensive driver would actually do — not what is technically permissible.
If you missed this question, that's exactly the right outcome of a practice session: the goal is to surface gaps before the actual test. Open your state CDL manual to the Coupling section and re-read the relevant subchapter. Then come back and run through the rest of the Combination Vehicles practice exam.