Overview
The G2 Axle and Gear JK CORE 44 front axle with a 4.56 ratio and ARB Air Locker (part C4JMFS456AP5) is for the 2007 and up Jeep Wrangler JK. G2 builds it on a high pinion 8.8-inch Dana 44 gear design with a new housing.
The housing is built to take heavy loads that would normally bend a stock Dana 30 or Rubicon Dana 44, and it is set up for aftermarket components of the owner’s choice, including lockers. The axle shafts are G2 Placer Gold, USA-made 35-spline Chromalloy. It is a direct fit that reuses the factory wheel ends and brakes, and the ARB Air Locker is part of the assembly.
Key features
- High pinion 8.8-inch Dana 44 gear design in a new housing
- ARB Air Locker
- USA-made 35-spline Chromalloy axle shafts
- Standard axle caster for 0 to 4 inch lifts
- Heavy-duty 3-inch diameter, 5/16-inch DOM tubes
- Heavy-duty 1/4-inch laser cut brackets and forged bearing caps
- Heat-treated aluminum differential cover with cooling fins
Choosing a gear ratio
A 4.56 ratio gives the front axle a lower gearing than a taller setup, which helps the drivetrain pull at low speed over rocks, steep grades and heavy tires. On the road the same ratio raises engine speed at highway speed, so many owners weigh fuel economy and noise against trail performance. The right choice depends on tire diameter, transfer case setting and how the vehicle is mostly driven.
An air locker engages both front wheels together, which keeps the vehicle moving when one wheel loses grip. Because the front axle also steers, the locker is best used at low speed and disengaged for everyday driving. Fresh gear oil and a check of the pinion preload after the first few trail runs help the gears wear evenly.
Specifications
| Brand | G2 Axle and Gear |
|---|---|
| Part number | C4JMFS456AP5 |
| UPC | 631410120356 |
| Position | Front |
| Housing type | 07-up Jeep JK Dana 44 |
| Gear ratio | 4.56 |
| Traction device | ARB Air Locker |
| Axle spline | 35 splines |
| Axle shafts | USA-made 4340 Chromalloy, 1.5 inch, 35 spline |
| Axle tubes | 3 inch diameter, 5/16 inch DOM |
| Wheel bolt pattern | Reuse factory ends |
| Brakes | Reuse factory |
| Fitment | Direct fit |
Vehicle fitment
It fits 2007–2018 Jeep Wrangler (JK) models.
This axle is built for the JK generation. Confirm your vehicle’s year, model and trim before ordering.
Installation notes
The factory wheel ends and brakes are reused, so installation is limited to the axle. A 4.56 gear set with a locker needs professional setup and break-in on a Dana 44. The standard caster setting suits lifts from 0 to 4 inches.
What’s included
The complete front axle assembly with the 4.56 gear set, ARB Air Locker and 35-spline Chromalloy shafts.
