NP231 Transfer Case

The Zumbrota Drivetrain RTC231J-12 is a remanufactured New Process 231 transfer case meticulously rebuilt to meet or exceed OEM specifications. Designed specifically for the 2000-2002 Jeep Wrangler TJ, this unit ensures reliable performance for your drivetrain. This transfer case features a 1.55-inch input shaft with 23 splines and a 27-spline output shaft that includes a rubber boot for added protection. Zumbrota Drivetrain rebuilds each unit to unparalleled standards, thoroughly inspecting cases and internal components for wear, cracks, stripped threads, shaft straightness, gear wear, and chain stretch. A proprietary Hydro-blast rinse and blasting procedure, followed by deep cleaning, prepares components before reassembly. Each RTC231J-12 is fully rebuilt with new bearings, seals, and viscous couplers. Finished units undergo rigorous spun testing to verify shift-ability and quiet operation. For transit protection, all transfer cases are shipped in high-density plastic totes. This unit uses a harmonic balancer on the rear output shaft (not included) and is equipped with a speedometer and a 2-pin indicator switch.