Fix a Known Weak Point: Jeep models equipped with NP231 transfer cases share one common vulnerability. The factory slip yoke rear output shaft. While adequate for stock street use, this design quickly becomes a liability once suspension lifts and larger tires are added, increasing stress on the rear output shaft and driveline components.Built for Lifted Performance: Rough Country's Heavy Duty Slip Yoke Eliminator Kit replaces the factory slip yoke with a fixed yoke design to dramatically improve driveline strength and reliability. By correcting driveline angles, this upgrade helps eliminate vibrations caused by suspension lifts while allowing the use of a double cardan CV driveshaft for smoother on-road driving and improved off-road performance.Trail-Ready Durability You Can Trust: Constructed from high-strength materials, this kit is engineered to handle the added load and abuse that lifted Jeeps encounter on and off the trail. This kit includes everything needed to properly modify your transfer case and requires Rough Country's extended travel driveshaft, which helps prevent driveline vibration and protects the rear output shaft from failure.