Slip Yoke Eliminator Kit for Jeep NP231

The Advance Adapters 231J Fixed Yoke Eliminator Kit is engineered to fit Jeep NP231 transfer cases, providing a heavy-duty solution for driveline concerns. This kit replaces the stock slip yoke with a fixed yoke design, which is crucial for lifted vehicles experiencing driveshaft vibration or angle issues. The upgrade features a new 1 3/8”-32 spline rear output shaft, ensuring proper engagement with compatible driveshafts. Constructed from durable 356-T6 heat-treated aluminum alloy, the tailhousing offers robust performance and longevity. The kit comes complete with a 1310 c.v. yoke, though other yoke styles may be available to suit specific needs. Included are all necessary bearings, fastening hardware, and detailed instructions to guide you through the installation process. The NP231 transfer case itself is a reliable, chain-driven unit with a 2.72:1 low range, often found in Jeep XJ, YJ, and six-cylinder ZJ models through 1995. Important considerations for installation include potential modifications to the driveshaft itself, as noted by Advance Adapters. For Jeep vehicles utilizing the early NP231 design (pre-1997), it is necessary to remove the needle bearings from the stock drive sprockets to ensure proper fitment and operation of this kit.