Peterbilt Model 579 trucks will now come standard with Jost JSK37 12-inch inboard air slide fifth wheels.
The inboard slider is 23 lb. lighter than previous models, and Jost refers to other benefits including ease of use and infinite adjustment possibilities.
Jost fifth wheels have only four moving parts and include a positive coupling design to ensure true connections. On contact, a spring-loaded steel locking bar automatically slides into position, securing the kingpin.
The cast ductile iron tip plates come with a five-year warranty.