I built this trans back in 2008. Built the previous one as well but lost it when the front slip yoke failed and took out the case....front and rear, in a rather violent starting line kaboom!

Anyway, my new one never felt as good 1-2. On the bottle, I could hardly feel 1-2. But it never quit.

So pulled the trans after taking a couple of years off. The pan was rather full of clutch material.

Got into it and the intermediate clutch is smoked. Bad. Friction material all but gone and warped steels. These were Red Alto and Kolene steels.

So trans gurus. I think I had a problem from the start. The forward and direct look perfect. So far, I know to check the intermediate piston seals and the center support bolt. What else can cause this? It appears that the apply pressure was low.

I understand that it will fail again if i don't fix the root cause.

Ron

 

What was mainline pressure? How much power/weight?

What pan?

What valve body?

 

Hi Jake,

Saw your post on Chevelles, I'll respond here.

I never measured the mainline pressure. Something I should have done when I noted the 1-2 shift seemed a bit soft. First time using the Alto/Kolene combo.
700hp most of the time, sometimes a 150 shot. 3600lbs.
Pan is a deep aluminum, I don't remember who made it.
Stock VB with Trans Go -3 shift kit. I also added the stronger Direct clutch springs. I did not install the governor lock springs, it still shifts itself.
Thus far I only have it apart far enough to get the clutches out.
I'll get it further apart in the next hour or so.

Appreciate the response.

Ron

 

I would ditch the TransGo kit while you are in there. Internally dual feed it.
It's not the problem with 2nd though.

What orifice size for 2nd are you using?

 

.133" is where it is drilled.

I have it all apart. Lip seals are fine in the intermediate piston. The center support bolt was tight. VB bolts were tight.

One thing I'm seeing is that the rear accumulator piston is lose in the servo piston bore. The seal ring (teflon or rubber) doesn't contact the bore.

Also, there is no spring on the rear servo apply pin, I am not sure why. I assembled it, and simply don't remember. Perhaps a remnant from a previous kit I had in here which was a B&M trans kit. I'm over 50.....

I'd ditch the TG kit, but I don't have the orig seperator plate. And I tend to get lost when trying to "undo" previous work....

Recommendation on frictions? I believe I will leave the forward and direct as is, they look great.

 

I use 4 Borg Warner High Energy frictions and .076" steels in the intermediate clutch pack. I don't use a wave plate. .133" orifice is fine when using stock servo configuration.

You can use the valve body as is with the TransGo mods, but a stock separator plate drilled or I have new seperator plates for the TH400.

I would re-install a servo spring.

The accumulator piston seals seperate intermediate (2nd) oil from accumulator oil. A leak here will cause intermediate failure.

 

Ah, so it seems I found the issue with the acumulator seal.
Just to make sure we are on the same page and I didn't use the correct descriptions.



I had a spare servo/acumulator "in stock" I need an outer seal for the accum piston.

Here are the burned up parts.



I'll do the dual feed mod if you will sell me the parts, discs, steels, seperator plate and that seal ring?

I appreciate your help.

Ron

 

We can set you up with the parts.

 

I sent you a PM

 

Just wanted to give a public thanks to Jake. I have my parts and am part way through the rebuild. We are removing the TransGo kit and dual feeding the direct clutch. Also setting it up with a 4 friction intermediate clutch. Plus a couple of other tricks.
Jake has been excellent to deal with.
So thanks Jake!

Ron