Challenge Cook Brothers 08 Gearbox Jam Nut 5/16"-18

Challenge Cook Brothers 08 Gearbox Jam Nut 5/16"-18

This is a 5/16"-18 UNC hex jam nut, specifically identified for use on Challenge Cook Brothers (CCB) 08 model gearboxes. A jam nut is a thinner-than-standard nut that is tightened against a primary nut to prevent it from loosening due to vibration, a common issue in heavy machinery like concrete mixers. This part is essential for maintenance and repair to ensure that critical components on the gearbox remain securely fastened during operation. The zinc-plated steel construction provides moderate corrosion resistance.

Key Features

• Specifically for Challenge Cook Brothers 08 gearboxes
• 5/16"-18 UNC coarse thread size
• Hex jam nut style for locking applications
• Requires a 1/2" wrench or socket for installation
• Zinc-plated steel for corrosion resistance

Fits These Mixers

ZF, Rex, PMP, Challenge, Bonfiglioli. Fits Challenge Cook Brothers model 08 gearboxes. It may be used on either the 12-bolt or 24-bolt variations of this gearbox.

All measurements ± standard manufacturing tolerance.

Product descriptions are drafted with automated tools and reviewed as time allows. While we work to keep them accurate, specifications and fitment should be confirmed with a Customer Service specialist at 800-745-3414 before purchase. Found an error? Let us know and we’ll fix it.