Inspecting Converter Dollies and the Second Trailer
Inspecting Converter Dollies and the Second Trailer
This domain checks whether you inspect the parts that are easy to overlook: the dolly and the trailer behind it. A defect there disables the whole combination.
Converter dolly inspection
- Fifth wheel jaws, locking jaws, and safety latch.
- Pintle hook or coupling to the lead trailer; safety chains present and crossed.
- Air lines and electrical cord; shut-off valves open.
- Tires, wheels, lugs, mud flaps, lights, and brake chambers.
- Landing gear and crank handle secured.
Second trailer inspection
- Kingpin and apron for cracks or wear.
- Air lines, glad hands, electrical cord, and lights.
- Brakes adjusted and not leaking air.
- Tires, wheels, and load securement.
- Doors latched and cargo covered.
Connection checks
After coupling, confirm the dolly fifth wheel jaws are locked on the second trailer's kingpin. Check that air pressure builds on the rear trailer and that the brakes apply and release.
Worked example
You hear an air leak at the dolly. Do not assume the lead trailer's system is fine. Close the shut-off valve, check the glad hand seal, and confirm the rear trailer's brakes still apply. If the leak continues, the combination is out of service.
Traps
Inspecting only the lead trailer, missing dolly tire damage, and failing to check that the rear trailer's brakes actually apply. A dolly with a cracked fifth wheel or missing safety chain is a defect, not a minor issue.