The GM TH400 automatic transmission adapter to the Jeep Dana 300 is 4.250” in length. The adapter material is 356 T6 heat treated aluminum alloy and has a provision for a transmission mount. The adapter kit includes an adapter housing, new 27 spline TH400 output shaft, 27x23 spud shaft, bearing, snap rings, gaskets, fastening hardware, and adapter instructions.
Note: Please specify when using the AMC TH400 version. The GM and AMC TH400 are similar, the difference is the AMC version has a rotated rear 6 bolt pattern.
The adapter assembly fits the1980-86 Jeep Dana 300. All 300s use a 23 spline input. 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.
This adapter kit is designed for exclusive use with the 4WD GM TH400 automatic transmission. The TH400 has a case length of 24.250” and a “Texas-shaped” oil pan underneath it. The factory output shaft has a spline count of 32 spline and had various output stick-out lengths.
Note: Our adapter kit is designed to replace TH400 output shafts with stickout lengths of 1.5” & 2.5”.