After you lock the kingpin into the fifth wheel, you should check the connection by:
Answer: C
Pulling the tractor ahead gently with the trailer brakes locked.
Upon locking the kingpin into the 5th wheel connector, slowly pull the tractor ahead with the trailer brakes locked to verify a secure connection.
All choices
- ABacking up with the trailer brakes released.
- BPulling forward 50 feet, turning right and then left.
- CPulling the tractor ahead gently with the trailer brakes locked.
Why the other answers are wrong
A. Backing up with the trailer brakes released.
Choice A is wrong because backing up with trailer brakes released does not test the secure connection properly.
B. Pulling forward 50 feet, turning right and then left.
Choice B is wrong because pulling forward 50 feet and turning does not specifically verify the locking of the kingpin.
CDL Combination Vehicles Test Info
Questions on Exam
20
Passing Score
80%
Time Limit
Typically 30 minutes; varies by testing location
The Combination Vehicles test content is federally standardized, so this question applies in every state. Age limits, fees, and testing procedures do vary — check your state's CDL requirements.
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More CDL Combination Vehicles Practice Questions
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