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
JOST Locking Mechanism
Anti-High Coupling Lugs
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 50,000 lbs and a maximum horizontal rating of 150,000 lbs.
All JSK37U Series literature is available below:
Top Plates
standard Top Plate - JSK37U Series
low lube top plate - JSK37UW Series
- Product Overview – [PDF]
- Operation Instructions – [PDF]
- Operation Instructions with Retractable Handle – [PDF]
- Operation Instructions with Air Release – [PDF]
- Maintenance Procedures – [PDF]
- Maintenance Procedures with Retractable Handle – [PDF]
- Maintenance Procedures with Air Release – [PDF]
- Other Important Procedures – [PDF]
- Product Bulletin – Low Lube Plate Update – [PDF]
- Parts List – [PDF]
Retractable Handle top plates - JSK37U B
Air Release Handle top plates - JSK37U A
Drop Handle top plate w/ Internal Adjustment - JSK37010 Series
Mounting Brackets
inboard “b” style mounting bracket (obsolete)
Inboard “u” style mounting bracket
Outboard Style Mounting Bracket
no-tilt style mounting bracket
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.
Replacement Parts
Bracket Pin Replacement - All 37 Series Wheels
Lock Jaw & Cushion Ring Replacement
Inspection & Maintenance Guidelines
Additional Service Tools & Parts
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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.
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JOST International is a world market leader for the commercial trucking industry. As a pioneer of efficient, safe, and innovative systems for trucks and trailers, we proudly supply fifth wheel couplings, trailer landing gear, kingpins, turntables, and more.
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