TH400/JEEP NP 23T(THIN)1987-94 NP231

Advance Adapter

Our Advance Adapter 50-6402 will allow you to adapt a GM TH400 3 speed automatic transmission to the Jeep NP231 transfer case. The adapter housing is 1.250″ 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 27 spline TH400 output shaft, new 27 spline NP231 input gear, gaskets, seal, fastening hardware, and adapter instructions.

Transfer Case

The adapter assembly will fit the Jeep NP231 transfer case. 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 231 only

Transmission

This adapter kit is designed for exclusive use with the GM TH400 automatic.

Bill Of Materials

• FLANGED NUT 3/8 -24 SERRATED PLATED / 302071
• ADAPTER- TH400 TO JP NP231 SHORT / 51-6401
• SHAFT- TH400 OUTPUT / 52-3200
• INPUT GEAR- NP231 27 SPLINE PRE 95 / 716202
• FREEZE PLUG 1.937 / 716165
• GM T400/4L80E 862-4709 GASKET / 716510
• GASKET-N.P.208 TRANSFER CASE / 716517
• SEAL CR#19466 / 716729
• 3/8 -16 X 1-1/2 S.H.C.S. zinc / 723740