Overview
The G2 JKRJRB513ARB is a Rock Jock Dana 60 rear axle assembly with 5.13 gears, an ARB Air Locker and the Big Bearing upgrade, built for the Jeep Wrangler JK. G2 Axle and Gear and Currie Enterprises built the assembly to order. It is made for 2007–2016 Jeep Wrangler (JK) models, in both 2-door and 4-door versions.
The housing is a Rock Jock high pinion design with a ductile iron center section. Currie’s rotated cover design and replaceable skid plate are part of the housing, and the skid plate is AR 400 heat treated steel. Inside, the assembly uses top shelf lockers and gears with Timken bearings and National seals. The axle shafts are 1 1/2-inch chromoly with 35 splines, and the tubes are 3-inch D.O.M. steel.
The Big Bearing layout and the Set 80 wheel bearings are what separate this version from the standard-bearing Rock Jock. The assembly accepts factory brakes and wheel sensors, and it has a dual bolt pattern that works with both 5 on 5 and 5 on 5.5 inch wheels.
Key features
- Ductile iron housing center section with a rotated cover design
- Replaceable AR 400 heat treated bottom skid plate
- ARB Air Locker for locking traction
- 5.13 gear ratio with top shelf lockers and gears
- Currie 35 spline chromoly axle shafts, 1 1/2-inch in diameter
- 1350 series yoke
- Set 80 wheel bearings and Timken bearings
- Dual bolt pattern for 5 on 5 and 5 on 5.5 inch wheels
- 3-inch D.O.M. steel tubes
- Accepts factory brakes and wheel sensors
Gear setup and locker use
A locker changes how an axle shares torque. With an air locker, both wheels on the axle turn together when engaged, which helps on steep climbs, loose rock and uneven ground. Off road, the locker is best used when traction is lost on one side, and it should be released for street driving so turning stays smooth. Gears and locker are best matched, since a locker puts extra load on the ring and pinion.
Because the gear set and locker arrive assembled, any later change to the gearing usually means a full ring and pinion job. Tire size, final drive and transfer case ratios should be considered together with the axle, and driveline angles should be checked after a lift or a major tire change.
- Check the air line and fittings for leaks before each trip
- Keep the axle breather and fluid level in mind during trail use
- Ask a gear shop to check tooth contact after installation
Specifications
| Brand | G2 Axle and Gear |
|---|---|
| Part number | JKRJRB513ARB |
| UPC | 631410100327 |
| Axle type | Rock Jock Dana 60, rear, high pinion, Big Bearing |
| Gear ratio | 5.13 |
| Axle spline | 35 splines |
| Axle shaft material and size | Chromoly, 1 1/2-inch, Currie 35 spline |
| Tubes | 3-inch D.O.M. steel |
| Center section | Ductile iron |
| Skid plate | AR 400 heat treated, replaceable |
| Yoke | 1350 series |
| Wheel bolt pattern | 5 on 5 inches and 5 on 5.5 inches |
| Wheel bearings | Set 80 |
| Traction device | ARB Air Locker |
| Brakes | Reuse factory |
Vehicle fitment
It fits 2007–2016 Jeep Wrangler (JK) models, in both 2-door and 4-door versions. A 2017 or 2018 model falls outside that range, so check the year before ordering.
Vehicles outside the 2007–2016 Wrangler JK range, including the JL, Gladiator, TJ, LJ and YJ, are not covered by this assembly. Check the year, model and trim against your vehicle before buying.
Installation notes
Driveshaft modifications may be needed to fit this larger 60 series housing. Ring and pinion setup and bearing preload should be done by a shop with gear setup equipment, since the lockers, gears and bearings arrive set up as one assembly.
What’s included
The assembly includes the Rock Jock Dana 60 housing with the ARB Air Locker, 5.13 gears, Currie 35 spline axle shafts and the 1350 series yoke.
Not included: an air compressor, which is sold separately.
