Built for Dana 60 axle builds running 40-spline shafts, this Yukon Grizzly Locker upgrade sends 100% of available torque to both axle shafts under load. Its ideal for heavy-duty builds that have stepped up to 40-spline axles and need a differential that can match that level of strength and abuse.

The patented gear design features larger engagement teeth and improved tooth geometry, significantly increasing strength and reducing common failure points. Built with 8620 steel internals and assembled in the USA, this locker is designed for long-term durability while still allowing disengagement during turns for improved drivability.

Includes:

• (1) 40-spline mechanical locking differential
• Fully assembled internal gear set
• Installation-ready unit for Dana 60 carriers

Specifications

• Fits Dana Spicer 60 differential
• 40-spline axle compatibility
• Carrier: 4.56 and numerically higher gear ratios
• Automatic mechanical locking differential
• 100% torque transfer under load
• 8620 steel internal components
• Patented gear design for increased strength and durability
• Larger internal teeth to resist shock load and breakage
• Assembled in the USA

Fitment

*Not compatible with C-clip axle applications

Tech Insight

Upgrading a Dana 60 to 40 spline axles significantly increases axle shaft strength, but requires a differential that can handle the added load. This locker is designed specifically for those builds, making it ideal for rigs running large tires and high torque setups.

Mechanical lockers like the Grizzly provide consistent traction by locking both wheels under load, which is critical in off-road environments. Proper setup, including backlash and carrier preload, is key to long-term durability and performance.