Author Topic: turbo 400 trans from 2x4 to 4x4 swap?  (Read 4048 times)

Offline xschroederx

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turbo 400 trans from 2x4 to 4x4 swap?
« on: September 09, 2014, 06:36:34 pm »
So I am parting out my 78 gmc and I want to give my transmission to him as he needs that same transmission. Problem is, the transmission is coming out of a 2 wheel drive, and he needs one for his 4x4. Is it possible to swap the trans?

Offline Engineer

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Re: turbo 400 trans from 2x4 to 4x4 swap?
« Reply #1 on: September 09, 2014, 08:06:11 pm »
Yes, you will need to remove the tail housing, change the output shaft, and drive a freeze plug into the hole where you take out the speedo drive from.

I assume "his" is a TH400 as well? If not that complicates things a bunch.
« Last Edit: September 09, 2014, 08:08:07 pm by Engineer »
2002 Chevy 2500HD 4x4 8.1/ZF6sp RC/LB
2001 Chevy 2500HD 4x4 6.0/4L85E EC/SB
1997 Chevy Blazer 4x4
1994 Chevy K-2500 4x4 C6P 5.7/4L80E
1979 Chevy K-30 4x4 4sp 4.10
1977 Chevy K-30 4x4 4sp 4.10 454

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Offline Irish_Alley

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Re: turbo 400 trans from 2x4 to 4x4 swap?
« Reply #2 on: September 09, 2014, 11:31:21 pm »
output shaft doesnt just come out. you have to take the inside of the trans apart to remove the outputshaft

it is posable to have the same shaft but you have to look at it i dont know what came in what
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Offline Blazin

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Re: turbo 400 trans from 2x4 to 4x4 swap?
« Reply #3 on: September 10, 2014, 06:35:42 pm »
If your gona tear apart the whole trans to swap the output shaft, you might as well rebuild the trans that has an issue.
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