Help with Th400 Valve Body

Reply Subscribe

Thread Tools

Search this Thread

Mar 19, 2007 | 07:16 PM

Silver00V6Camaro

Thread Starter

Drifting

Joined: May 2004

Posts: 1,258

Likes: 0

From: Huntsville Alabama

Help with Th400 Valve Body

Ok i have a transgo 400 1-2 reprograming kit. I was able to get back to work on completeing this today. Well i forgot where these parts go in the valve body and i can not find my instructions for the transgo kit. The haynes manual for th400 does not help much either. Here are the pics. Thanks in advance for helping.

the parts

The factory springs

the transgo springs

Mar 19, 2007 | 08:52 PM

Vettenstein

Advanced

Joined: Oct 2003

Posts: 64

Likes: 2

From: OK

I don't have a scanner, but I took photos of the transgo sheet for you. I left them in hi-res. (6MB)

http://www.wikiupload.com/comment.php?id=106848

Mar 19, 2007 | 09:05 PM

Silver00V6Camaro

Thread Starter

Drifting

Joined: May 2004

Posts: 1,258

Likes: 0

From: Huntsville Alabama

thanks downloaded and saved incase i loose them again. I actuall found my instructions about an hour ago. so now here is a pic of the parts i do not remeber where they go in the valve body.

update pic

Mar 19, 2007 | 10:45 PM

Vettenstein

Advanced

Joined: Oct 2003

Posts: 64

Likes: 2

From: OK

I haven't torn into mine yet, so can't help from here. I'll bet someone will come along soon that can. Good luck.

Mar 20, 2007 | 12:07 AM

TimAT

Le Mans Master

Joined: Oct 2006

Posts: 7,123

Likes: 433

From: Gladstone MO

C3 of Year Finalist (appearance mods) 2019

You need either the GM unit repair manual or the ATSG THM400 book.
Both should show the valve body in enough detail to get everything back together.
..
Next time, swap springs and valves one at a time too. I built trannys for GM dealers for about 10 years, did lots of them at home, and never took apart more than one chain at a time.. Even the little caps over some of the valves are picky about which way they are installed.
Not trying to be an a**, but valve bodies are a little finicky..

Mar 20, 2007 | 01:12 AM

7T1vette

Team Owner

Joined: Jan 2006

Posts: 37,637

Likes: 3,118

From: Crossville TN

The springs can be very tricky to identify. There was a color code on all of the springs which defined where they went in the valve body. The whole spring is painted one color; then, many of them had a different color stripe (about 1/8" wide) running the full length of the spring. The stripe paint quite often flaked off, and it becomes difficult to sort them out. The heated oil also discolored the lighter colored base paint on the springs. Be careful with the valves also. Some of them look like they are symmetrical, but, in fact, the length of the valve lands can be only a few thousandths of a inch longer...or the diameters are almost the same. The valves have to go into the proper bore and in the right direction. Without the right instructions, you have a very difficult task. You may end up having to get an assembled one out of a junk yard and disassemble it piece by piece to know where those parts should go. Your best bet would be to go to a transmission repair shop who has very good disassembly/reassembly manuals for the THM-400 and see if they will loan or rent them to you.