Fifth Wheels

JSK37U  Series

JSK37U Series Fifth Wheels Overview

The JSK37U series is JOST’s flagship line of cast ductile iron fifth wheels that is a standard specification option at every OEM. This series features the original locking mechanism that all other JOST fifth wheels are based on and sets the industry standard for fifth-wheel construction and functionality. Designed with safety and operator efficiency in mind, the features included in the JSK37U line are included in all other JOST fifth wheel products.

  • Available with a cushion ring or steel wear ring
  • Infinite adjustment
  • 3-Point Locking System
  • Anti-high coupling lugs
  • Requires only 60lbs of force to open
  • Can be rebuilt on truck in 30 minutes without removing the top plate

Key Features & Benefits

JSK37U  Series

Replaceable Cushion Ring

A replaceable cushion ring reduces the lifetime cost of ownership. JOST parts across product lines ensure affordable, consistent product availability.

JOST Locking Mechanism

JOST’s signature 3-point locking system features three locks with just four moving parts to ensure ultimate safety & simplicity.

Anti-High Coupling Lugs

Innovative anti-high coupling lugs prevent drivers from high coupling by either guiding the kingpin into the jaws or pushing it up and over. This allows for a clear indication when the fifth wheel is properly coupled.

Download the jost fifth wheel catalog

A comprehensive look into each of the JOST fifth wheel products.

Parts, Assemblies & Specs

JSK37U  Series

JOST’s JSK37U Series is available in standard, air release, and low lube top plate options, all of which seamlessly pair with a range of mount styles to suit any commercial trucking application. The JSK37U series has a maximum vertical rating of 55,000 lbs and a maximum horizontal rating of 150,000 lbs.

All JSK37U Series options are available below:

Bracket Exchange Program

The JOST Bracket Exchange Program offers additional flexibility. JOST will send a new bracket to you, in return of your current bracket.

Please call Customer Service at 800-253-5105 to learn more.

Inspection & Maintenance Guidelines

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Request Info

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Warranty Statements

Claims should be filed with JOST or any authorized sales or service outlet within 60 days of product failure.

Support Help

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