PSC Steering SG688R Big Bore XD2 Cylinder Assist Steering Gearbox for Jeep JK 07-18

2007-2018 Wrangler JK/JKU 

• 45MM Sector Shaft
• NEW XD-JK Proprietary Pitman arm
• 16:1 Ratio 80MM Piston Assembly
• Reinforced Mounting Pad and Case

The BIG BORE XD-JK with Cylinder Assist™ Ports is the most powerful and strongest replacement steering gear 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 XD-JK, when combined with our PK38JP1 or PK36JP1 Pump Kit, provides up to 35% more turning power over the factory steering gear.

The sector shaft diameter has been increased from 35MM to 45MM to handle the extra torque output and prevent shear in severe environments. Every Big Bore XD-JK Steering Gear includes a NEW proprietary Pitman arm designed for the larger sector shaft. When adding an Assist Cylinder Kit to your project, the SG688R already includes the Ports required to power it. 

Improved on-the-road driving characteristics and significantly increased torque output are achieved by using a 16:1 80MM piston assembly. This increased torque output will turn tire sizes up to 35" without the installation of cylinder assist, and will enable you to enjoy superb on-the-road handling as well as tackle 5-10 rated trails with ease.

RECOMMENDED INSTALLATION TOOLS:
46mm Pitman Arm Nut Socket
Pitman Arm Puller
Axle Caster Gauge
Tie Rod End Puller
Pneumatic Anaerobic Thread Sealant

INSTALLATION NOTES:
WARNING! Add the HWK-688-PP Bolt Kit (110MM Long) when installing any Synergy MFG Front Track Bar Brace (or similar) with this product.
Using the Factory bolts (90MM Long) or the PSC supplied bolts (100MM Long) with a Synergy MFG Track Bar Brace could result in steering gearbox case failure.

WARNING! This product weighs approximately 57 lbs. Work safely and avoid physical injury by using appropriate lifts/tools and/or utilizing the assistance of a work buddy 

The BIG BORE XD-JK Steering Gear requires a power steering pump capable of approximately 1650 PSI. PSC highly recommends the use of a HIGH FLOW/HIGH-PRESSURE Pump Kit to ensure system efficiency and extend component life. These pumps operate at approximately 1650 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:

PK38JP1: JK/JKU 3.8L High Flow Pump Kit
PK36JP1: JK/JKU 3.6L High Flow Pump Kit

The larger size of the BIG BORE XD-JK Steering Gear may not fit with first generation aftermarket track bars. We recommend scheduling a consultation with a Professional Installer for an evaluation and an appropriate solution determination.

The supplied PSC proprietary Pitman arm does not have any additional drop to it.
Some applications may require a drag link flip kit for proper installation.