It’s not every day that we extend the deck on a big rig and rebuild the fifth wheel.
The fifth-wheel coupling provides the link between a semi-trailer and the towing truck, tractor unit, leading trailer or dolly. The coupling consists of a kingpin, a 2-or-3+1⁄2-inch-diameter (50.8 or 88.9 mm) vertical steel pin protruding from the bottom of the front of the semi-trailer, and a horseshoe-shaped coupling device called a fifth wheel on the rear of the towing vehicle.
This modification was done to accommodate greater space between the cab and the trailer giving the rig more room for storage.
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