NP231 Slip Yoke Eliminator SYE Kit from Alloy USA Fits Vehicle: ◾Fits 1997-2006 Jeep Wrangler TJ with NP231 transfer case ◾Fits 1988-1995 Jeep Wrangler YJ with NP231 transfer case ◾Fits 1987-2001 Jeep Cherokee XJ with NP231 transfer case This is a MUST if you installed a 3" or taller suspension lift in your 1987-2006 Jeep® Wrangler. The purpose of this kit is to shorten the transfer case length and replace the slip yoke portion of the NP 231 with a fixed yoke. By shortening the transfer case length it allows for a longer rear double cardan-style driveshaft which reduces the driveline angle. This reduces or eliminates the vibration and lengthens U-joint life. This kit from Alloy USA includes a re-designed transfer case main shaft which is not only shorter, but has an 18% larger spline diameter, which gives it a 54% increase in torque capacity. Kit includes a new aluminum rear output housing, bearings, seals, snap rings, bolts and detailed instructions. This is the most complete and strongest kit available. After install you will need a new CV style longer driveshaft. We offer driveshaft kit 16592.01,16592.04 and 16592.05 available separately. Alloy USA PN: 1140 Reference#: 52231 18676.60