5r55e Forward clutch air testing

[EricB123]

First off I don't know what I'm doing. I've not rebuilt a transmission before and I'm following this site, youtube and the rebuild manual for the 5r55e.

I'm working on a transmission with a destroyed forward clutch. I bought a forward clutch drump used because the gears on the original were chewed up, but both clutches (original and replacement) seem to leak around the center support when I'm air testing them. There is some side to side wiggle with the center support and the drum and it seems like all the air is leaking out of the center support section and not the clutch piston (which was also rebuilt).

The leak was less when I replaced the seals on the center support and the fit is better. I can get the clutch to move, but it still leaks. Is it likely the center support is too worn or could the seals be the wrong size?

 

[EricB123]

I was just wondering if anyone has experience testing this setup for leaks. Is this a common problem. One guy who sells used parts on ebay tried the test said:

He couldn't get it not to leak when he tried just putting the forward drum in the support. When he did that it leaked every time. He ended up putting the direct drum on with both thrust bearings. One on top of forward drum and one between the direct drum and support. Along with some lube on the sealing rings so nothing was dry. When I checked it that way no leak.

Is this due to worn parts, or is this air test just difficult to do?

 

[BrooklynBay]

Did you use a plastic seal protector on the rings? Lubegard makes something called Seal-E-Zee which is a set of cones, and 2 types of freeze sprays. Check this link for more information: http://www.lubegard.com/~/C-295/LUBEGARD+Seal-E-Zee+Application+Cone+Set

 

[EricB123]

Do you mean use the seal protector for the two rings around the bearings? This is the area that seems to be leaking. Shown in this photo:

https://imgur.com/a/y4QjD

I don't think the piston seals are leaking, at least not nearly as much as the seals that slide into the center support seem to be. Is it uncommon for this test to have leaks:

https://imgur.com/a/vEymC

(FYI this image from the manual is the same for piston removal and for testing once assembled)

 

[BrooklynBay]

All of these seals are fragile, and could be easily damaged while they are installed. That's why they make special seal installation tools. If any of these seals are missing or leaking, it could cause a major decrease in line pressure with a no engagement situation. You could find OTC/Rotunda seal installation drivers for this transmission on EBay.

 

[EricB123]

Thanks for your help. The seals that appear to leak are the hard rings as shown in the images. I don't think the seal install kit is for those.

1. Is this test realistic? I've noticed others mention they need 40 psi to move their clutch (test says 20 psi max).
2. Other people tell me that they need to add lubricant and include the direct drum to keep the hard seals from leaking for this test.
3. Do the hard ring seals also need an install kit?

 

[BrooklynBay]

The hard seals don't need a special installation kit since they have a mitered split. They are able to collapse while they are installed. I would assume that the split causes them to leak since there's a gap in the sealing area.

 

[JK080]

Some leaking is expected around the rings but the bottom line is the clutch has to work with as minimal leaking as possible. Try to squirt transmission fluid in the hole in the center support before applying air. Make sure the sealing ring surface in the support is not damaged and that the air for your test is coming through the support correctly.

The sealing rings on the support are not used for the forward drum and no need to install the direct drum to air check the forward drum on the support