SM420 X JEEP DANA 300 and NP231 T/C

Advance Adapter

This adapter kit will allow you to adapt the GM SM420 4 speed manual transmission to the Jeep Dana 300 transfer case. The adapter is 5.250” in length and is made from strong 356 T-6 heat treated aluminum alloy. We also supply a mounting provision on the bottom of the housing to use our heavy duty transmission mount PN716021.

The adapter kit includes a adapter casting, spud shaft, snap ring, set collar, gaskets, fastening hardware, and adapter instructions.

Note: This adapter kit can also be used with the Jeep NP231.

Transfer case

The adapter assembly will fit the Jeep Dana 300. This transfer case was used in the 1980-’86 CJ-7 series. All 300s use a 23 spline female input shaft. Some of the adapters we manufacture include a new Dana 300 input with a different input spline. Therefore, if you obtain a Dana 300 from a salvage yard, please verify the input spline.

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.

Bill Of Materials

• GASKET SET-MUNCIE SM420 TRANS / 716508
• GASKET-N.P.208 TRANSFER CASE / 716517
• NUT 3/8 -16 PLATED GRD 5 / 723701
• SHAFT- SM465 SPUD TO NP231 23SP / 52-9700
• SNAP-RING EXT, INPUT-SHAFT GEAR / 716453
• SET COLLAR- 2 PIECE 1-3/8 2PC / 716454
• H.H.C.S. 3/8 -16 X 1-1/4 (GR5) zinc / 723722
• ADAPTER- SM420 TO DANA 300 / 51-9702
• LOCK WASHER 3/8 ZINC / 723704
• STUD BOLT 3/8 -16 X 2-3/4 / 723710
• STUD BOLT 3/8 -16 X 2 LG B7 / 723711