Author Topic: 700r4 to th400 swap..(possible or not)  (Read 3832 times)

Offline overthepond

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700r4 to th400 swap..(possible or not)
« on: May 21, 2008, 04:22:36 PM »
Hey guys..!

I just picked up a 84'Suburban 2wd with the 350 and a fried 700r4.
I also have a known to be ok th400 in the shed that i want to use to replace the fried tranny.
What am i up against in the swap,basically any info on what will or wont fit,what i'll need and if its worth the hassle and trouble.
Many thanks in advance.. ;D
Dave
When all else fails...try again.

Offline zieg85

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    • 73-87 GM squarebody extended cab and conversions up to 91 R/V series
Re: 700r4 to th400 swap..(possible or not)
« Reply #1 on: May 21, 2008, 05:47:12 PM »
Check the length of the transmissions and compare.  You may need a different/altered drive shaft.  TH400 use an electric kick down as far as I can remember.  Cross member will need to be moved but holes should be in the frame for the new position.  If it is a true TH400 the rear output is different and requires a different yoke.  They made a TH375 that looks just like a 400 but the rear output is the same as the TH350/700R4.  I am sure there are other considerations and others will chime in.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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