This infographic demonstrates the coupling and uncoupling items that you will need to inspect during the Pre-Trip Inspection portion of your CDL Skills Test.
![CDL College Truck Driving School Coupling and Uncoupling Inforgraphic CDL_College_Truck_Driving_School__Coupling_and_Uncoupling_Inforgraphic](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiqkxT6nZrFdwLLM_9s7c1h_vL4VzjCDk4VHApGDZdFC60z0zUMWblXOvrVv7b3cy4eiX_lWwQdVtGjLcJ5EdI8QVlR38D1nYSATd0lu1SplwjwGQ-hjfUoBev4d_PfizQrTFxv8xwOvz4/s1600/CDL_College_Truck_Driving_School_Coupling_and_Uncoupling_Inforgraphic.png)
CDL College Inforgraphic Download
Watch the complete Trailer Inspection Video
Air/Electric Lines
- Listen for air leaks.
- Check that air hose and electrical lines are not cut, chafed, spliced.
- Make sure air and electrical lines are not
- pinched, or dragging against tractor parts
- Check that electrical plug is firmly locked in place on both tractor and trailer.
- Check that air connectors are sealed on both tractor and trailer.
- Mounting Bolts. Look for loose or missing mounting clamps, bolts, or nuts.
- Locking Jaws. Look into fifth wheel gap and check that jaws are fully closed around the kingpin.
- Fifth Wheel Skid Plate. Check fifth wheel skid plate for proper lubrication and mounted to the platform. Also ensure that all bolts are secure and not missing.
- Platform. Check for cracks or breaks in the platform that supports the fifth wheel skid plate.
Release Arm and Safety Latch
- Make sure the release arm is in engaged position and the safety latch is in place.
Kingpin/Apron/Gap
- Check that the kingpin is not bent.
- Make sure the visible part of the apron is not bent,
- cracked, or broken.
- Check that the trailer is laying flat on the fifth wheel
- skid plate (no gap).
Sliding Fifth Wheel Locking Pins
- If equipped, look for loose or missing pins in the slide mechanism of the sliding fifth wheel. If air powered, check for leaks.
- Make sure locking pins are fully engaged.
- Check that the fifth wheel is positioned properly so that the tractor frame will clear the landing gear during tuns.
CDL College Inforgraphic Download