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Coupling and Uncoupling Combination Vehicles
Knowing how to couple and uncouple correctly is basic to safely operating a combination vehicle. Wrong coupling and uncoupling can be very dangerous, leading to a dropped trailer or a separation on the road. This chapter walks through the fifth wheel, kingpin, landing gear, and air line connections, and the exact sequence to connect and disconnect a tractor and trailer safely.
Inspecting Combination Vehicles
Combination vehicles have coupling and trailer components that must be inspected in addition to the normal tractor checks. This chapter covers the fifth wheel and coupling system, the trailer air lines and brakes, and the trailer's tires, lights, and suspension. A careful pre-trip inspection catches problems that could cause a separation, brake failure, or breakdown on the road.
Driving Combination Vehicles Safely
Combination vehicles are longer, heavier, and handle differently than smaller vehicles, and they can roll over or jackknife if driven carelessly. This chapter explains off-tracking, rollover prevention, trailer skids and jackknifing, and safe following distance. Understanding how the trailer follows the tractor helps you turn, brake, and steer safely.
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