What should be a priority after locking the kingpin into the fifth wheel?

After locking the kingpin into the fifth wheel, checking the connection's security should indeed be a priority. This step is crucial because ensuring that the kingpin is properly secured to the fifth wheel hitch is fundamental to safe towing. A loose or improperly locked connection can lead to a catastrophic failure while the vehicle is in motion, potentially causing accidents or losing the trailer entirely.

Verifying the connection includes checking that the locking mechanism of the fifth wheel has engaged correctly and inspecting the area around the kingpin for any signs of improper connection. This verification helps to confirm that the trailer is safely attached to the tractor before the vehicle sets off on the road.

While inspecting the tractor, checking trailer lights, and verifying air pressure in tires are all important safety checks, they can be performed after ensuring that the hitch connection is secure. Prioritizing the security of the connection lays the foundation for safe operation of the combination vehicle, as it directly relates to the integrity of the entire setup.