TH400 problem need pros help.
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From: port st lucie florida
Yeah I wonder why the trans builder which I'm unsure of the name so I'm not going to say but there were alot of things done right in the trans and then you come to the sprag and you just have to wonder WTF were they thinking here? It doesn't make sense that the trans was built as nice as it was just to put one inferior part in that many know would cause a failure.
I'm looking for info on the GER transbrake valve body, so far not good. It's all aluminum, this thing doesn't require gaskets between it and the sep plate and case?
And the center support has a brass steady rest ring on it. That seemed to tear up the aluminum drum. It's going to get an iron drum but I don't want that to tear that one up too. (looking for an iron drum still, anyone?)
For the intermediate pressure plate snap ring it had a circlip type thing with a retainer. I'm used to the big fat ones from transgo.
And the center support has a brass steady rest ring on it. That seemed to tear up the aluminum drum. It's going to get an iron drum but I don't want that to tear that one up too. (looking for an iron drum still, anyone?)
For the intermediate pressure plate snap ring it had a circlip type thing with a retainer. I'm used to the big fat ones from transgo.
Last edited by Jays_SSZ28; Jan 30, 2018 at 08:01 PM.
That last picture you have there Jay is a case strut. Not sure who makes that one but they are a good idea for added support for a nice wide snap ring. I have seen a few different designs. I find that the pressure plate flex's in this area in the case do to the lack of support from the case lugs.
I personally don't understand the brass ring on the center support. The only thing I can think of is someone was trying to use it as a bushing for support. There are other ways to do this however it requires some machine work and installing bearings. The big issue I see with it is the aluminum drum did not like it! I personally have never used anything like it. As far as the drum you said iron drum. Are you just looking for a stock sprag style drum? Kind of confused sorry. Vince
I personally don't understand the brass ring on the center support. The only thing I can think of is someone was trying to use it as a bushing for support. There are other ways to do this however it requires some machine work and installing bearings. The big issue I see with it is the aluminum drum did not like it! I personally have never used anything like it. As far as the drum you said iron drum. Are you just looking for a stock sprag style drum? Kind of confused sorry. Vince
Jay the brass ring shouldnt have much of an affect on an iron drum due to the iron being harder than brass. . I stocked up on the th400 sprag drums before they were hard to find. kinda funny if you bought it as a th400 drum and they came with 34 element sprags also they were 39 bucks but if you got a 4l80 drum they were 100 bucks I loaded up on the 39s. I also have a few of the lug sprag front planets I doubt i will get rid of those though, kinda hard to find these days
The brass ring is a steady rest, ATI sells a center support like that.
I happened across a supply of new sprag type drums. You have to watch the old ones for wear and in some cases they have been reground and won't hold up in a performance application.
I happened across a supply of new sprag type drums. You have to watch the old ones for wear and in some cases they have been reground and won't hold up in a performance application.
Seems they were big on th400's because I found at least 15 of the old sprag drums, the 4L80E drums, even two new in the box, and I had a few of the sprag type front planetaries too. There was even some switch pitch stuff there just to name a few parts I ran accross.
Not to mention the th350, 700 parts I got.
At the time I was buying th400 cores for $40 like some damn obsession. I built a few for people.
Eventually I threw a lot of the parts right in the trash, and sold most of my cores and those old drums that were left.
What really sucks is I sold the last drum I was holding onto and a box of new parts (soft parts kit, set of bushings, bearings, thrust washers, selective washers, new rear band, etc and leftovers from other kits) sold the drum, sprag and race for $35, and a 12x12x6 box stuffed with the parts for $37, ebay.
If I kept that stuff and had some frictions this thing would be up and running by now. Instead the parts are on order.
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From: port st lucie florida
I'm just glad there was not more damage. We will get it up and running again soon thanks to Jason. If this were a 6 speed or a T-5 I would know what to do but I'm not an auto guy.
