904 differences

[cannucky]

what is the difference internally between the pre and post 72 904 transmissions ?

[fishy68]

As far as I know 72 wasn't a year of much change. What are you wanting to know?

[cannucky]

thanks Fishy , the race rebuild kit I bought for my 904 is sold as a 72 and up kit , I bought the billet drum and 24 spring return module kit as well so that all works fine but I was wondering about the seals and bushings as the new stuff naturally looks a little different from whats in it . I'm just trying to do as much as possible before I do the swap and would hate to put a wrong seal in it and have to pull it back out and redo it .
PS I'm not even positive it's the origional tranny but if it is it's in a 69 so should be a 68 part I believe

[fishy68]

Gotcha. Wish I could help more but my 904 experience is very limited. Done a truckload of 727's but only a couple 904's. You might try PM'ing 70aarcuda and see if he has any ideas what might be different. He's rebuilt a lot of 904's. Good luck

[TrailBeast]

Maybe let someone that does it do it if it looks to foreign.

Just tryin to save you some headaches and money.

[cannucky]

Originally Posted by TrailBeast

Maybe let someone that does it do it if it looks to foreign.

Just tryin to save you some headaches and money.

the important stuff is already done ,just looking for info from those that do know not negative talk from those that don't .

[cannucky]

Thanks Fishy I'll send him a PM

[fishy68]

Your welcome Cannucky

[70aarcuda]

go over to moparts....i know...PM John_Kunkel

he knows more about torqueflites...then chryslter..

http://board.moparts.org/ubbthreads/...0&fpart=1&vc=1

[oldkimmer]

.................Whats the #s on the pan rail on the drivers side........r u putting a shift kit or manual vb........can u post some pics of the differences u found........does the billet drum have a wider bushing in it than ur other 1........if so u need the back half of the new style pump..............kim........

[TrailBeast]

I wasn't trying to be a ahole or negative.
Ya just never know how much a person is capable of doing.
Glad the important stuff is done.
Myself, I have probably only done 60-70 of them and was just trying to save you some possible headaches.
I see oldkimmer is already on it about the drum and pump part if thats what you were needing to find out.

Originally Posted by cannucky

the important stuff is already done ,just looking for info from those that do know not negative talk from those that don't .

[cannucky]

Originally Posted by oldkimmer

.................Whats the #s on the pan rail on the drivers side........r u putting a shift kit or manual vb........can u post some pics of the differences u found........does the billet drum have a wider bushing in it than ur other 1........if so u need the back half of the new style pump..............kim........

The billet drum is listed as correct for my year , it and the return module setup are sold separate from the rebuild kit , It already has the transgo-2 kit in it and a stock pattern valve body so I haven't changed that out I just wanted to upgrade to the better drum with more clutch's and of course the red eagle and kolene steels ,which worked out great as far a disc clearances in the pack go and the kevlar band fits perfect , the better clutches and steels fit perfect in the rear drum as well , the only real difference I can see in the kit is the rear and front seals just look a little different from the older ones in the tranny now but as I said they are new and I expect a heavier duty part than a stock rebuild but I figured I should ask before swapping the tranny into the car .
The seals in the tranny are still good so I can just ignore this and not remove the old ones, but it never hurts to ask about something that looks a little different thats how we learn new things eh !
Trailbeast - No harm No foul

[70aarcuda]

you can put 5 alto red and kolene steels in the 4 disc drum....you need the .061 thickness disc..and .068 thickness kolene steels..you need at least .060 clearance in the front drum...

i usually set my at .070....i take the pressure plate to a machine shop and he surfaces/grinds it .010 to get the extra clearance...

I have done 4 904s like that....3 are being used...one in reserve...

[cannucky]

Originally Posted by 70aarcuda

you can put 5 alto read and kolene steels in the 4 disc drum....you need the .061 thickness disc..and .068 thickness kolene steels..you need at least .060 clearance in the front drum...

i usually set my at .070....i take the pressure plate to a machine shop and he surfaces/grinds it .010 to get the extra clearance...

I have done 4 904s like that....3 are being used...one in reserve...

The billet drum I`m useing has a relocated groove for the lock ring to accomplish this very thing , the Guy`s at TCS were very helpful when I did the clutch packs , they recommend .010 per clutch disc with no more than an extra .010 on the total ,this after soaking the discs for at least an hour , I left mine soaking over night and the Wet stack worked out .005 over the .010 x The # of discs which they told me over the phone was perfect .

PS sorry for the vagueness on some things I actually did this rebuild last fall after getting back from my journey I just haven't gotten to swapping the trannys yet . I'm trying to get all my ducks in a row before I do , the new lines should be here soon and I'm going to do the swap then , can't wait to feel the push of the tighter converter and this trans was already a go-er when it was behind the stock 318 I never should have gotten talked into trading it for the 727 that's in the car now .

[70aarcuda]

i usually check the clearance with the disc dry.....but there is more then one way to skin a cat...lol

[PoisonDart74]

Hey, good job for doing this man. F the naysayers.

[cannucky]

Originally Posted by 70aarcuda

i usually check the clearance with the disc dry.....but there is more then one way to skin a cat...lol

I was thinking that when I read your post and they told me some people do it that way but it requires more math skills than multiply x 10 eh ! lol . Plus I seem to remember I actually traded 1 thick front disc for 2 of the thinner rear disc's to get the good number or maybe it was 3 for 2 I really don't remember either way it was what they recommended as any time you can get an extra disc in it is better than the thicker single disc , they send you 5 or 6 of each in the kit and I think I swapped 1 thick into the rear drum to get the number there otherwise you are swapping lock rings till you find one that is right or machining plates to get the good number .

[cannucky]

I just found a download on there site that shows an exploded view of the 904 if anybody want's a reference pic to look at while doing it themselves , I don't know how to link sites but they are at TCSproducts.com , they manufacture several of there own parts and race a 1400hp car with a 904 in it .

[cannucky]

Originally Posted by PoisonDart74

Hey, good job for doing this man. F the naysayers.

That's what this site has really been all about , the rest of the personal and political crap is just that crap , which is of course why I troll those guys on a fairly regular basis lol

[TrailBeast]

http://tcsproducts.com/media/1/TCS_A...arts_Nov11.pdf

[cannucky]

Thank TrailBeast and if you look at the bottom of the page in the pic of the rebuild kit you can see the 2 seals I am talking about they are red and green and located right under the kevlar band in the pic

[oldkimmer]

............Ya, thats been the style for a number of years in the aftermarket........front seal i use, but u can still get the rear seal from the dealer that has the dust boot on it............kim.........

[cannucky]

thanks Kimmer I went home and looked at all of the stuff I have left over and looked at the tranny and figured it out but was wondering about the dust boot , the old one was torn about half off so I guess I'll call the dealer and see if there is one with the boot here on the island , looking at the two ends it looks like I can do both of those pretty easily so I think I'll do it for the sake of having new and I'm good to go .

[TrailBeast]

When I was doing them they were changing over to the no dust boot style.
We ALWAYS used red locktight and a seal retainer on the front pump seal
This way we NEVER had a seal pop out on a hard run.
They are only about three or four bucks and worth every penny.
They just tap down over the pump housing and hold the seal in no mater what.

I don't see much mention of them normally, and I think it's because no one really knows about them exept the guy's that have had a seal pop out after it was all back in the car.

Originally Posted by oldkimmer

............Ya, thats been the style for a number of years in the aftermarket........front seal i use, but u can still get the rear seal from the dealer that has the dust boot on it............kim.........

[oldkimmer]

...............Almost every chevy tranny has seen that seal retainer..........kim........