The BIG BORE XD2 is the most powerful and strongest replacement steering gearbox on the market for the Jeep JK. Any Jeep JK with larger tires and/or locking front differential needs this bolt-on upgrade. The BIG BORE XD2, when combined with our PK1858 XD Pump Kit, provides up to 35% more turning power over the OEM steering gearbox.
The sector shaft diameter has been increased from 35MM to 45MM to handle the extra torque output and prevent shear in extreme duty environments. Every Big Bore XD2 Steering Gearbox includes a NEW proprietary Pitman arm designed for the larger sector shaft.
NOTE: Some applications may require a tie rod flip kit as the Pitman arm does not have any additional drop to it.
The mounting pad of the BIG BORE XD2 has been up significantly reinforced to reduce frame flex, unwanted sector shaft deflection, and to prevent catastrophic failure of the case, resulting in a steering gearbox that weighs 15 LBS heavier than the OEM component.
Improved on-the-road driving characteristics are achieved by using a 16:1 ratio 85MM piston assembly. Also, the much larger 85MM piston assembly delivers significantly increased torque output. This increased torque output will turn up to 37"; tall tires without the installation of cylinder assist.
RECOMMENDED INSTALLATION NOTES:
The BIG BORE XD2 Steering Gearbox was designed to be used with a power steering pump capable of 1800 PSI.
PSC highly recommends the use of their HIGH FLOW/HIGH-PRESSURE Pump Kits to ensure system efficiency and extend component life. These pumps operate at approximately 1800 PSI and produce 50% more volume than the OEM pump. Vehicle steering performance will be diminished if a high mileage or remanufactured component is used.
PSC recommends the use of a power steering fluid cooler and SWEPCO 715 Power Steering Fluid.
The larger size of the BIG BORE XD2 Steering Gearbox may prohibit the use of some aftermarket track bars.
Pitman Arm Retaining Nut Size: 46MM
HEMI Engine Conversions: If the AC compressor or power steering pump is located on the bottom driver side of the engine, there may be clearance issues.
GM LS3 Engine Conversions: The alternator will need to be modified for clearance.