01
Kingpin definition
The trailer pin that locks into a tractor’s fifth wheel.
In commercial driving, the exact legal or technical application can depend on vehicle configuration, cargo, operating authority, and state rules. Drivers should confirm requirements in the current official CDL manual and applicable federal regulations.
02
Practical example
Before departure, the driver inspects the kingpin to confirm it is correctly positioned, connected, and safe for the load.
03
Why Kingpin matters
Correct use and inspection protects the driver, the freight, and other road users while reducing damage and roadside violations.
04
Frequently asked questions
What does Kingpin mean in trucking?
The trailer pin that locks into a tractor’s fifth wheel.
Why should CDL drivers understand Kingpin?
Correct use and inspection protects the driver, the freight, and other road users while reducing damage and roadside violations.
Where can I learn more about Kingpin?
Review your state’s official CDL manual, use ELDT Info study resources, and ask a qualified instructor how the term applies to the vehicle or operation you plan to drive.