SmithCo introduces kingpin housing design

SmithCo has introduced a new patent-pending kingpin housing that the company says will provide longer life with fewer maintenance costs than traditional kingpin housings. SmithCo specializes in-side dump trailer design and manufacturing, The new kingpin housing will be included with all SmithCo over-the-road side dump trailers beginning in 2025.

The company emphasizes dump trailers are hard on kingpins, which connect a trailer to a fifth wheel and allows the trailer to pivot and maneuver behind the vehicle. As side dumps haul dirt, gravel, riprap, and other material, they often are filled to a maximum payload. Between the starts, stops, and dump cycles, the trailer’s kingpin sees a lot of stress over the course of months and years of use.

SmithCo reported customers are often forced to choose between removable kingpins that wear out, or weld-in kingpins that are harder to remove, costing owners extended downtime and increased shop costs. The company said its new solution will combine the best of both worlds. The new collet-style kingpin housing offers the security and durability of a weld-in kingpin without needing a plasma cutting torch to replace the kingpin. The patent-pending design locks the kingpin in solidly for an expected safe and reliable connection.

Dan Dohman, SmithCo’s director of engineering, commented, “Our engineers developed a collect-chuck style kingpin housing that presses together and locks everything in place. This design secures the kingpin and eliminates movement without requiring the kingpin to be welded to the fifth-wheel plate. The results are a stronger, more durable connection that extends the life of the kingpin and reduces maintenance costs.”

SmithCo worked with Iowa State University’s structures lab to perform accelerated life testing of the new kingpin assembly. Simulating 500,000 fully loaded start/stop cycles, they fatigue-tested the new design to prove it outlasted previous designs. After the half-million cycles, the kingpin showed no signs of movement within the housing.

The new patent-pending design will arrive at dealerships in 2025. More information is posted on www.SideDump.com.