Before coupling the semi trailer, you should inspect the condition of the kingpin as well as the kingpin plate. Also ensure the wheel chocks are firmly in place behind the trailer wheels to prevent the trailer from moving and determine whether or not the trailer has spring brakes.
The trailer is now ready to be coupled:
- Make sure the fifth-wheel jaw is open and the wheel horns are tilted down.
- Slowly back the tractor squarely up to the approach plate of the trailer. Do not hit the plate.
- Set parking brake before leaving the power unit.
- Check height of semi trailer in relation to the fifth-wheel. Adjust the height by use of the trailer landing gear.
- Check alignment of kingpin and fifth-wheel on tractor.
- Check that cargo in the trailer is secure, and that no one is inside the trailer or behind it1.
- Release parking brake. Back slowly under the trailer until fifth-wheel engages kingpin.
- Make sure coupling is secure by pulling tractor ahead slowly but firmly. Do not move trailer as this may cause damage to the landing gear.
- Apply parking brake.
- Visually check to see that the jaws of the fifth-wheel are properly locked and around the kingpin, and the safety lock is in position.
- Connect air hoses and electrical cord.
- Wind up landing gear fully replacing handle in the stowage bracket.
- Check trailer sliding tandem to ensure lock pins are in position.
- Check to ensure tractor sliding fifth-wheel locking device is secure.
- Remove wheel blocks.
- If the trailer has service brakes only, connect the light cord and both air hoses to the trailer. Ensure that emergency and service lines are not crossed. Ensure draincocks are closed on air tanks. Open trailer protection valve to charge trailer with air. Apply trailer brakes using hand valve. ↩