Part of this years build is to make a NP231 doubler
This is how I did it.
Original plan was to get my hands on a NP231C from a GMC Jimmy but with some thought and some research it was realized that I could use some parts I had around to put this together.
I decided to blend an NP241C and a NP231J to make the doubler.
The 241
The 231
---------- Post added at 07:17 PM ---------- Previous post was at 07:14 PM ----------
Since there was a spline difference between the 23 spline input of the 231 and the 29 spline output shaft of 4L60 4 speed automatic transmission. It was necessary to replace the input of the 231 with the input of the 241.
Here are some of the pictures and comparisons of the two transfer cases.
This is the 231.
Input planetary gear.
The output shaft.
The 241
Input planetary, output shaft and case.
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