If your wanting to run large 37” tyres and use the Jeep off road, upgraded axles are essential. This was the main focus for this Jeep.
The Standard front Dana 30 axle was removed and replaced with a G2 Core 44 Axle.
The American-made CORE 44 front axle housing uses the latest generation Dana 44 gear design, with a larger diameter ring gear and bigger pinion shaft to withstand hard off-road use. This axle housing features forged bearing caps and a unique G-lock adjuster nut system to set backlash and carrier bearing preload. CORE 44 axles use additional ribbing on the cast center section and 3-inch diameter, 5/16-wall DOM axle tubes with forged inner Cs perfect for use with the tall, aggressive Cooper tyres. All brackets are designed around stock mounting points, and are laser cut and CNC formed from 3/8-inch steel for added strength. They also gusseted and reinforced any weak points to prevent damage to the brackets.
Large 37” tyres on the factory 3.21 ring and pinion gears results in poor performance, lack of control off road and increased strain on the engine and transmission. To improve acceleration and gain low speed off road control, the ring and pinions were swapped out for 4.88 ratio to compensate for the larger tyres.
The Wrangler is fitted with the world’s most highly regarded traction aid, an ARB Air Locker. The Air Locker is a driver controlled locking differential originally designed to give serious 4 wheelers the traction needed to combat extreme off road terrain. When extra traction is required, the driver activates the Air Locker via a convenient dash mounted switch. Pneumatic pressure supplied by an on board air compressor engages ARB’s patented locking mechanism within the Air Locker, thus preventing the wheels from turning independently. The Air Locker is deactivated by flicking a switch, returning the differential to normal.
ARB Air Locker’s patented design has proved ultra dependable, even in the most arduous conditions. It’s strength lies in its simplicity minimal moving parts ensures maximum reliability. All structural components are manufactured from aerospace grades of high alloy steel.
The ARB compressor used the run the Air Lockers can also be used for tyre inflation, mounted in a convenient location with a long air line hose suitable for reaching all 5 tyres.
The aftermarket ARB locker accommodates stronger and larger 35 spline drive shafts. We used G2 Placer Series axles which are manufactured in the USA to provide the strongest solution for the Jeep. Forged from high grade 4340 chromoly, and heat treated with computer-controlled methods, which results in 25% deeper surface penetration over stock. This allows them to withstand the loads produced by larger tyres and low gear ratios. The gold zinc plating aids in added corrosion resistance.
The standard Dana 44 axle has been re-geared to 4.88, ARB air locker installed with 35 spline Chromolly Drive shafts.
The Jeep is fitted with Huge 37” x 12.5” Cooper STT Pro tyres with 17” Hutchinson beadlock wheels:
To increase the mobility of the Jeep operating on poor traction surfaces such as sand, mud, rocks or snow, it is necessary to increase the footprint of the tyres. This is achieved by decreasing the tyres air pressure. This mobility is only achieved if the wheels are equipped with a tyre bead locking device as the tyre pressure can be taken down to single psi figures without risk of the tyre popping off the bead. Hutchinson’s wheel design allows the use of internal beadlocks, keeping them street legal.
Old Man Emu 4” suspension lift kit by ARB has undergone countless hours of engineering and testing.
4 inch lift is achieved by linear rate springs using X5K high grade steel tuned to provide compliant ride on road while maintaining off road performance.
Both front and rear Nitrocharger Sport shocks have vehicle specific valving tuned for optimal blend of ride control and comfort. Shock lengths have been optimised for maximum down travel while retaining factory drive shafts.
A flipped drag link has been used to reduce the angle of the steering drag link which will increase life of steering joints and improve steering control. The G2 axle has a higher track bar mount to maintain parallel relationship between the track bar and high steer drag link.
Stainless Steel braided brake hoses are longer than standard to cope with increased suspension hight and travel.
In addition to the Old Man Emu Kit, advanced geometry control arm drop brackets have been used. These durable drop brackets help reset JK control arm angles to a more natural and comfortable geometry. By reducing the operating angle of the front control arms, the force applied to the arm when hitting a bump is now directed up into the springs instead of being absorbed into the frame. These drop brackets allow the JK with 4in of lift to operate more like stock, with a more appropriate geometry to increase force on the front wheels. More force means more traction in straight line braking and reduced weight shifting and inertia when braking during a curve.
The rugged ridge hurricane fender flares give an aggressive off-road look and tyre clearance. The flat fender design was inspired by earlier concepts and specifically the 1941 Willys MA. The double bolt pockets with black stainless fasteners provide a modern twist on the traditional flares.
It was necessary to trim the rear wheel arch pinch seam to eliminate the tyre rubbing on full suspension compression.
Mopar HD bumper provide increased protection and functional recovery points. The Front bumper houses a M800 warn winch and features a Grill guard.
Teraflex HD rear tyre carrier is essential for supporting additional weight of the huge spare tyre on the rear door.