Th400/205 swap

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Tyler Rea

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I’ve been working on this project for a while piecing it together. I dropped the th350/203 setup I had and now I’m nearing the end of the th400/205 swap. I’ve ran into a problem. The 400 is out of a humvee and has a 32 spline output shaft and the 205 is out of a dodge with 23 splines. I cannot find any couplers that will work for these splines. Am I going to have to change either of the shafts or am I just not looking hard enough for the right coupler?
 

climb-101

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you have to change the shaft in the transfer case. advanced adaptors makes the setup, you will also have to machine the case to accept the bigger bearing that the 32 spline shaft needs.
 

nvrenuf

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In addition to this ^^, you need to identify the length of the th400 output shaft (measure how much sticks out of the case) in order to know which adapter and which np205 input shaft to get (long or short).
 

Tyler Rea

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St. Helens
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Tyler
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1976
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GMC K/2500
Engine Size
350 5.7
you have to change the shaft in the transfer case. advanced adaptors makes the setup, you will also have to machine the case to accept the bigger bearing that the 32 spline shaft needs.

Awesome thanks for the info
 

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