727 Valve Body Disassembly Findings

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billytuffnuts

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Hey Everyone,

I pulled apart the valve body from my 727 to install the TF2 Shift Kit and I came across a couple of concerns while cleaning it. Since I'm not too familiar with VB's I'm hoping some of you can give some advice. I'm also planning on having a trans shop put it through their parts washer as brake kleen doesn't seem to be working as well as I had hoped.

1) On the top of the VB, between the 1-2 & 2-3 shift valves, I found some kind "crud" in a valley (red rectangle) and when scraping it off, the bottom layer was copper and has the texture of copper anti-seize. After removing it I found a hole in the casting (yellow circle).

Should this hole be here? And what could this copper stuff be/why would it be on my valve body? I later found it in a couple of other spots including in the transfer plate passages (very little - see red circles

ValveBody.jpg


2) I noticed a defect (hole) in one of the pockets on the transfer plate - It doesn't look to be part of any passage but I'm not sure if I need to be worried about it or not.

Transfer Plate.jpg
 
I should also add that I haven't really experienced any issues with the transmission/valve body prior to taking it apart
 
The fact that the trans is shifting properly says volumes to me. The one area you circled looks like a manufacturing defect, which is not in an area that would cause you problems. A rebuild shop could have used anti-seize compound that washed off into that area where the crud was. Again, if it is shifting OK, don't sweat it. Clean the VB up and follow the shift kit instructions to the letter. Take your time and you will have a nice shifting unit when finished.
 
The fact that the trans is shifting properly says volumes to me. The one area you circled looks like a manufacturing defect, which is not in an area that would cause you problems. A rebuild shop could have used anti-seize compound that washed off into that area where the crud was. Again, if it is shifting OK, don't sweat it. Clean the VB up and follow the shift kit instructions to the letter. Take your time and you will have a nice shifting unit when finished.

I agree with your statement, I could just not for the life of me figure out why that copper stuff was in there. I finished up the shift kit install, just need to put it back in the trans and cross my fingers

The copper stuff is bushing and thrust washer wear. How much endplay does it have?

I did just replace a tailshaft bushing that looked like it had some wear on it. Unfortunately the trans in still in the car so I don't believe I can check that.

The valve body is not original to the trans so it could even be from the trans that it came out of.
 
I like it that it took GM several DECADES to catch up to Chrys & start using alum for valve bodies!!
 
Aluminum valve bodies are bad. That's the whole problem with old Fords. Aluminum valve bodies with screens instead of filters. Particles cause furrows to form in the aluminum by the steel valves. So, where steel valve bodies wear away, aluminum valve bodies get raised ridges in them; causing the valve to stick. To fix aluminum valve bodies and governors, you have to use an abrasive to wear away the aluminum raised furrows.
 
Completely disagree that alum v/bodies are bad.
They might have been in Ferds. Maybe a Fred engineering problem, wouldn't be the first time....
Chrys alum v/bodies are very reliable & trouble free.
 
The only difference between Ford and Chrysler aluminum valve body problems is that Chrysler went to a dacron filter, while Ford kept using the brass screen. My C4 builds all get an adapter to use a Chrysler dacron filter. They are then equal in their valve sticking problem. However, the th350 and th400 use steel valve bodies, and they are the most trouble free vbs out there I have seen, even with just screens. Some al vbs use aluminum valves as well; total disaster.
 
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