For recreational vehicle owners, a reliable fifth-wheel hitch is essential. It provides a comfortable ride and better control when towing your RV.
Unlike gooseneck hitches, fifth wheels are built to be safe and rated for heavy loads. They feature a kingpin that slots into the trailer’s plate and locks in place.
The First Fifth Wheel
There’s a lot of history behind the fifth wheel hitch that lives in the bed of your pickup truck. The basic design is a large, thick plate shaped like a horseshoe or half donut that rests on multiple rails that are secured and installed to the frame of your pickup truck for strength. The trailer connects to this hitch via a downward-facing pin (also called the kingpin) that locks into place.
The modern fifth wheel draws its name from an old system used on four-wheel carriages and wagons when horse-drawn loads were the norm. These old systems often had a horizontal “fifth wheel” that allowed a front axle to pivot. The result was the first successful fifth-wheel coupling that allowed fleet owners to attach trailers easily and quickly to trucks while drivers kept moving on their routes.
The Second Fifth Wheel
A fifth wheel is an oversized trailer hitch that attaches to a semi-truck tractor and allows the cargo on a trailer to be hauled behind it. It evenly distributes the weight of the cargo so a semi-truck can make turns quickly on the road.
The u-shaped hitch is secured to the bed of a truck or tractor and has a slot that accommodates the trailer’s kingpin. The hitch rests on hinges and can pivot, making it much easier to maneuver a trailer than if it was attached to the vehicle’s front wheels.
There are a variety of different types of fifth-wheel hitches. Some are fixed into place and can’t move, while others have a system that cushions against bumps or jostles in the road. Some have two-way pivot heads, which can move back and forth, making them easier to use on uneven roads.
Other options include a custom rail hitch, which doesn’t require holes to be drilled in the truck frame and has a single jaw that makes for an easy connection.
The Third Fifth Wheel
A fifth-wheel RV is a vehicle towed behind another vehicle, usually a truck. The name “fifth wheel” stems from this trailer having an additional point of contact in the back of the towing vehicle — the U-shaped hitch.
Various market trends drive industry demand for fifth wheels, including best-in-class pickup towing capacities and an increased desire for lightweight fifth-wheel towing options.
The Fourth Fifth Wheel
A fifth wheel is a ‘U-shaped coupling component that attaches to the back of the towing vehicle, such as a truck or semi. It is typically larger than a gooseneck hitch and can support a heavier trailer. It is the typical ‘connection of choice’ for tractor-trailers.
The earliest versions of these hitches were not a complete circle and used a metal headblock and a kingpin. These units were often hand-forged and required incredible audacity to use. Today, these parts are welded or bolted to the frame of a truck through a “pin box” on the back of the bed. It is vital for fleets to regularly inspect, clean, degrease, and lubricate their fifth wheels.