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Coupling and Uncoupling

Coupling and Uncoupling is a required knowledge area under 49 CFR 383.111(c)(1). The fifth wheel mounting and locking requirements tested here are directly codified at 49 CFR 393.70(b).

Practice Coupling and Uncoupling

4 Questions

  1. Under 49 CFR 393.70(b)(2), what must every fifth wheel assembly have to prevent the tractor and trailer from separating during normal operation?
  2. After backing the tractor under a trailer and confirming the fifth wheel has locked onto the kingpin, what should the driver do next to check that the coupling is secure?
  3. After supplying air to a newly coupled trailer and confirming normal air pressure, how does the manual say a driver should confirm the trailer's brakes are working before driving away?
  4. Under 49 CFR 393.70(d), what is required, in addition to the tow-bar itself, when towing a full trailer or converter dolly?