th400 schematics? best place?

[silverscottsk10]

I'm in need of a good th400 schematic and manual to study and get some information from. any help is appreciated

 

[Milblazer]

I've heard this is one of the best books available for helping with a TH400 but it is expensive:
http://www.amazon.com/Modify-Hydra-Matic-Transmission-Motorbooks-Workshop/dp/0879382678

The books from ATSG could help too:
http://www.amazon.com/Techtran-Manual-Automatic-Transmission-Service/dp/B000HZTJ9G

Free is always nice as well.,CUCV TMs. Open the PDFs and after they load click on the 5-1 section for transmission and transfer case.

The -20 is for simple things like changing the filter and other bits that can be done without removing the transmission from the truck.
http://www.jatonkam35s.com/CUCVTechnicalmanuals/tm9-2320-289-20.pdf

The -34 is much more in depth about the TH400.
http://www.jatonkam35s.com/CUCVTechnicalmanuals/tm9-2320-289-34.pdf

 

[chengny]

TH400 Shop Repair Manual - 1980 (60 pages):

http://depositfiles.com/files/6vvj420h0

If you are not familiar with file sharing sites, a tutorial on how to download for free from Depositfiles can be viewed at the bottom of this thread:

http://www.gmsquarebody.com/forum/showthread.php?t=6290

Cover page of the TH400 section of the manual:

 

[chengny]

And the 1987 version (46 pages):

http://depositfiles.com/files/jzvtotmyt

 

[chengny]

As for wiring diagrams, the TH400 doesn't have much electrical input. The downshift solenoid is about all I can think of. I doubt you have a variable pitch stator and I don't believe the TH400 ever had any TCC option. According to the GM shop manual, here is the list of all external controls (electrical and otherwise):

EXTERNAL CONTROLS
The external control connections to the transmission are:

1.Manual linkage to select the desired operating range.
2.Engine vacuum to operate the vacuum modulator unit
3.An electrical signal to operate an electric detent solenoid.
4.A stator solenoid to "switch the pitch" or stator angle. This device is used only with transmissions having a variable pitch stator.



Anyway, here are the diagrams for the 4WD indicator light (actually the switch is mounted on the transfer case) and the downshift solenoid:

 

[silverscottsk10]

I just wanna know what makes it go for the most part and install a shift kit and stall converter in it eventually and if anything goes wrong I'm not out 1800$ to a shop
It I'll look through these tomorrow guys
Thanks

 

[silverscottsk10]

As far as electrical i know there's not much
I'm looking more for the internals and parts and everything of that sort