Rear Assembly for Jeep JK

JK ProRock™80

The ProRock60 has long been the benchmark to which axles have been measured. When looking for the King of axles you had to look no further than the now-legendary ProRock60. As the off-road world has evolved, Dynatrac has raised the bar again with the introduction of the new ProRock80!

The lightest axle in its class, the ProRock80 has all the beef you’ll need in your JK to handle the largest tires with the hottest motor. Designed to handle just about anything you can throw at it, the ProRock80 has the strength to get you there and back. The ProRock80 is based off of the massive Dana 80. We took the best features of the Dana 80, added in the best features of our ProRock design and ended up with an axle that can handle the toughest terrain.

Our ProRock80 housing is designed for real-world conditions with real-world abuse. A low pinion design, the ProRock80 is ultra sleek but incredibly rigid. With an 11.25” ring gear and a 2” diameter pinion, the ProRock80 has unequaled strength in the 4x4 world. Add in 40 spline 4340 full floating axle shafts and you have an assembly that can handle huge tires, a massive rig and a heavy right foot.

No other axle in existence can handle this much torque, have this much ground clearance, and be this lightweight.....PERIOD!

  • 100% designed, manufactured and assembled in the USA
  • Lightest axle assembly in its class
  • Full floating axle design eliminates weight load on axle shafts
  • Unmatched housing rigidity to keep gears in proper mesh
  • 11.25" ring gear and 40 spline axle shafts can handle heavy weight, big horsepower and an aggressive driver
  • Sleek ProRock® housing keeps you sliding over the obstacles, not grinding to a halt
  • Most ground clearance of any axle using a 10.5" gear or larger
  • Integrated upper suspension mounting points
  • Proprietary, in-house developed forgings, housings, spindles, etc
  • CAD designed CNC cut brackets expertly welded for precise fit every time
  • Exclusive Dynatrac JK ABS and Stability Control compatibility
  • 1 year, unlimited mileage, "No-Fault", written warranty- real warranty- not empty promises
  • Exclusive high clearance custom machined Dynatrac ProRock80® standard cut heavy duty nodular iron housing
  • Heavy duty 4" diameter, 1/4" wall lightweight high rigidity Chromoly axle tubes
  • Axle width- 68.5"
  • Matched housing geometry and pinion angle for vehicle's suspension
  • Dynatrac Jeep JK heavy duty 3/16" rear coil spring brackets installed
  • Integrated upper mounting points for flexible link suspension
  • ARB Air Locker differential- 40 spline
  • Massive 11.25" ring gear with 37 spline pinion input shaft
  • Choice of USA-made Dana 80 standard-cut ring and pinion ratio 3.54-5.38
  • Dynatrac Dual Sump/High volume/High Pinion Angle Oil Modification (recommended for 11 degrees or more pinion angle)
  • 1410 input yoke
  • 8 lug (8 on 6.5") wheel pattern
  • Dynatrac ProRock80 heavy duty full float nodular iron wheel hubs, chromoly heat treated spindles and serviceable bearings
  • Heavy Duty J8 Military 13.9" vented rotor disc brake assemblies
  • Dynatrac JK ABS/ESP retrofit
  • Dynatrac ProMax 40 spline 4340 chromoly full floating axle shafts
  • Full Spool- 40 spline
  • 3/8" or 1/2" wall axle tubing
  • ARB high output compressor kit (CKMA12)
  • 1480 pinion yoke
  • GL-5 gear oil installed


JK ProRock™80