Our Advance Adapter 50-6801 will allow you to adapt a GM TH350 3 speed automatic transmission to the Jeep NP231 transfer case. The adapter housing is 1.50”” in length and is manufactured from 356-T6 heat treated aluminum alloy. We also supply a mounting provision on the bottom of the housing to bolt-on our heavy duty transmission mount (716008). The adapter kit includes an adapter housing, new TH350 21 spline output shaft, bearing, gasket, seal, o-ring, fastening hardware and adapter instructions.
Note: When using a transfer case that has a long input shaft of 2.12” stickout,the new TH350 output shaft may need to be shortened.
The adapter assembly will fit the Jeep NP231 transfer case with a 21 spline input shaft. This input shaft protrudes from the face of the transfer case 1.19” or 2.12”. Introduced in 1988, the Jeep NP231 is a part-time transfer case became the standard for XJ and YJ models. It was also used in six cylinder ZJ models through 1995. Chain driven with a 2.72:1 low range, it’s reliable even with more than stock horsepower applied.
The Advance Adapter kit is designed to fit Jeep New Process / NVG models 207, 231 with 21 spline input shafts.