Inspection of a 904 torqueflite

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They probably kept dropping it into low one to compensate for a worn forward clutch. The low reverse drum (the one in the back) can be swapped with your 904 drum so no prob. The front drum is the direct drum, front drum, or reverse high drum. How's the ring surface of the direct drum? Could you post a pic.


So far I haven’t checked the direct yet. I don’t have the pump out. From what I see......since the kickdown band is loose. I think it’s in great shape on the outer surface.

We will have to see what the inner race looks like where the cast iron seals sit. And how the clutch pack looks.
 
Might have some dead thrust washers? I wondered why it was not riding on the band surface

I won’t soak them.

Can I take the pump off by just screwing in bolts and marring the front case. ....or should I hit it with a slide hammer or chain.

Last time I just see a bolt in and put a circular mark in the gasket surface
..should be a sealing problem.....but I don’t know for sure
 
squirt oil around the pump then you can pry between the direct drum and sun gear shell..VERY GENTLY. Pry, tap the pump back in, pry again. Pry down along side the drums reaching down int the trans one side then the other. Squirt more oil around the pump before you tap it back in.
 
ok.....I just checked the play on that.

That line.....

I can slide the whole drum up easily by hand until that line meets the reverse band...

That’s a truck load of play
 
There’s a couple of things going on with this transmission.

The reverse drum is heavily worn......but the band is new

The pump has no washers......they were siliconed in.

All the clutches and steels look new. The gaskets were still soft and the speedometer o ring was a different color.....and was soft. It’s been replaced. Both inside and out.

The tail shaft housing was siliconed into place...no gasket.
The output shaft bearing is solid

Out put shaft has gouges cut in it from the cast iron rings.

The thrust washers all have copper left in them and the input shaft washer is complete copper color.

The endplay was checked before removing the parts. .030 was the total end play. Way in spec.....basically new spec

Front pump seal was replaced.....

Torque converter replaced

Gear sets are in the same condition as the ones I took out of the old one.....planets are tight and don’t wobble.....

Steel casing 4 planet

3.8 band lever with wider band......looks new. No material missing.
Looks after market.

As you all saw.....the fluid is black as it gets.

Like I said before......I could move the reverse drum 1/4” with the transmission standing on the bell housing. Might be normal....I don’t know.

I think I’m dealing with a fresh total rebuild that went wrong in some places....or they left the reverse drum worn down.

Other than those things......it seems fine.

The tail shaft housing is standard length. I’m going to compare the looseness of the other 904 to this one on the looseness of the governor and snap rings.

The man outpushaft thick washer......snap ring wore a groove in it as well....same as the other one....complete copper color on the back.

All the clutches are accounted for. Even the top steels look new.

What caused whatever did that to the reverse drum. I’m guessing that’s where the steel in that filter came from.

Of course I’ll post lots of pictures.

I think by buying this.....I just saved a bunch of money and got a really solid 999 that needs some attention.
 
Sorry....the 1/4” of play is on the reverse drum.....not the forward.

I can move the reverse drum up 1/4”. Maybe the output shaft land is worn. I’ll put the stack of the 904 and the 999 stack and see what’s what. Get a measurement and see why it moves like that

On the 904.....the reverse drum surface area that’s machined sits above the area that’s in machined..

On this 999 the machined surface sits below the in machined.

There are no hot spots anywhere. None of the steels.

The 5 friction have a larger waffle pattern as well. Not the smaller ones like the 904 has
 
Well.......this is the A999 transmission with a lock up clutch.
It has the lower gears, 5 friction direct clutch drum, 4 friction forward drum. We will have to see what shape the Simpson set it in.
The converter was replaced 5/14......

The wider direct band seems fine and the drum seems ok so far with just the pictures below.

Would you run that converter? If it’s only 5 years old.....the hub should be better and not crack but what do I know. That fluid being black.....Im thinking run it and inspect soon after.

The forward drum is shot. It’s worn down to finger nail catching.....is that shot? It’s too worn for me. I won’t run it. The other 904 has the 4 friction forward drum.....so I’m good on that.
What would cause that? Maybe bands not adjusted correctly. No one spends that much time in reverse.

View attachment 1715360317
Here is the magnet from the new transmission. The other 904 didn’t have one of these. I have 2 of them now. One was sitting it the van. So......why not run 2-

View attachment 1715360318
This doesn’t look good.....some metal shavings in the filter. I’ve never seen one so black. -

View attachment 1715360319
It’s a lock up clutch. I like this function as I’m just cruising this car.
What does the wire do? I grabbed the whole harness that went all the way to the fire wall. Might go into the fuse box.....I dunno-

View attachment 1715360320
Here’s an issue. The reverse drum is worn. I can catch a finger nail on it. It might be completely shot. -

View attachment 1715360321
a larger direct band. -

Fluid was pitch black.....and given that forward drum.....of course it is.

Hopefully this is in good shape. Or good enough that it won’t matter for what I use it for and how much it’s driven.

Gentleman.....I cannot thank you enough for teaching me and guiding me through all of this. I was gonna wait till pay day, but it could have been crushed by then.

All that’s left that I want to do is a mild cam and this build will be as far as it goes.....maybe 188/160.....but what would that really accomplish right now with the stock 76 compression.

I will hit that with the dial indicator and cc the heads to see what that is
You cannot use a forward clutch drum from a non lock up with a lockup. The sealing ring diameter in the stator is a different size.
By forward clutch I assume you mean the 2nd drum from the front.
They look identical but they are not. If you put a forward drum from a non lockup into a lockup trans you will end up with a no drive condition. It will assemble together, but the sealing ring diameter is .060 smaller on the non lockup drum and you will have a huge hydraulic leak. This drum is one of the fundamental differences between a lockup 904 and a non lockup 904.
 
Thrust washers start out gray and wear down to their copper center. So; you have all thrust washers worn down past the gray and no washer on the pump and you still have only .030 endplay....NO WAY. "Out put shaft has gouges cut in it from the cast iron rings." (?).. "The man outpushaft thick washer......snap ring wore a groove in it as well....same as the other one....complete copper color on the back." (?) Yes pics please.
 
On the forward drum and direct drum. I’m pretty sure it’s good. The only problems I have found so far are the reverse drum that has all the wear around the band surface area.

Are you talking about the direct drum being a bigger diameter....the number 1 behind the pump?
The direct drum and forward drum look right. I’ll compare them with pictures of the different measurements on them.....length, width and race diameters......as well as stack clearances and thrust measurements. One of these drums might not be long enough. Having the 904 here disassembled helps a lot because it’s just a little worn out and had nothing wrong with it.

the 1/4” movement. When the transmission is standing up on its bell housing. I can move the reverse drum up 1/4” off the bottom of the sun shell.....this picture is the reverse drum and band. I can move that drum up so that line meets the band. So far that’s the only thing strange I see and it might be normal to do that.
48225654012_61c56b21a6_m.jpg
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All the washers are present. It has a fiber washer on the pump and the one on the clutch hub. They haven’t been measured yet. I think this transmission is gonna need more measuring than the last.
I would have have done it last night for peace of mind..... but after driving 2 hours and taking that thing out in the hot sun....I was done.

The 999.....someone was in there and there’s no telling what they did. They messed something up I’m sure and that’s why there is metal in the filter like that. I think what they messed up is from the reverse drum back.....or maybe replaced 999 stuff with 904 stuff that looks right but isn’t. This is the mixing and matching Cuda is talking about.....they might have done that. I don’t think so but I won’t assume in this case.
 
On the forward drum and direct drum. I’m pretty sure it’s good. The only problems I have found so far are the reverse drum that has all the wear around the band surface area.

Are you talking about the direct drum being a bigger diameter....the number 1 behind the pump?
The direct drum and forward drum look right. I’ll compare them with pictures of the different measurements on them.....length, width and race diameters......as well as stack clearances and thrust measurements. One of these drums might not be long enough. Having the 904 here disassembled helps a lot because it’s just a little worn out and had nothing wrong with it.

the 1/4” movement. When the transmission is standing up on its bell housing. I can move the reverse drum up 1/4” off the bottom of the sun shell.....this picture is the reverse drum and band. I can move that drum up so that line meets the band. So far that’s the only thing strange I see and it might be normal to do that.
View attachment 1715360500 -

All the washers are present. It has a fiber washer on the pump and the one on the clutch hub. They haven’t been measured yet. I think this transmission is gonna need more measuring than the last.
I would have have done it last night for peace of mind..... but after driving 2 hours and taking that thing out in the hot sun....I was done.

The 999.....someone was in there and there’s no telling what they did. They messed something up I’m sure and that’s why there is metal in the filter like that. I think what they messed up is from the reverse drum back.....or maybe replaced 999 stuff with 904 stuff that looks right but isn’t. This is the mixing and matching Cuda is talking about.....they might have done that. I don’t think so but I won’t assume in this case.
When talking about the clutches and drum,you have to be sure of your terminology. The forward clutch or drum is the second
Drum from the pump. If i interpreted you correctly, you said that drum was bad(which it usually is not) and that you had a good one from the non lockup. If that's what you meant I am saying you cannot do that. In my opinion at this point you need to decide whether you want to build a lockup or the non lockup trans.
The only difference between the two is the valve body, the input shaft, the forward clutch, and the stator are unique to the lockup.
The first drum behind the pump is called a couple of names,high gear or direct. The forward drum only goes by the name forward.
The rearmost drum is usually called the low/reverse drum. It is not used in reverse only.
Everything from the sunshell and back is the same in the lockup and non lockup. The shape of the low gear sunshell is unique but it assembles the same way.
 
On the forward drum and direct drum. I’m pretty sure it’s good. The only problems I have found so far are the reverse drum that has all the wear around the band surface area.

Are you talking about the direct drum being a bigger diameter....the number 1 behind the pump?
The direct drum and forward drum look right. I’ll compare them with pictures of the different measurements on them.....length, width and race diameters......as well as stack clearances and thrust measurements. One of these drums might not be long enough. Having the 904 here disassembled helps a lot because it’s just a little worn out and had nothing wrong with it.

the 1/4” movement. When the transmission is standing up on its bell housing. I can move the reverse drum up 1/4” off the bottom of the sun shell.....this picture is the reverse drum and band. I can move that drum up so that line meets the band. So far that’s the only thing strange I see and it might be normal to do that.
View attachment 1715360500 -

All the washers are present. It has a fiber washer on the pump and the one on the clutch hub. They haven’t been measured yet. I think this transmission is gonna need more measuring than the last.
I would have have done it last night for peace of mind..... but after driving 2 hours and taking that thing out in the hot sun....I was done.

The 999.....someone was in there and there’s no telling what they did. They messed something up I’m sure and that’s why there is metal in the filter like that. I think what they messed up is from the reverse drum back.....or maybe replaced 999 stuff with 904 stuff that looks right but isn’t. This is the mixing and matching Cuda is talking about.....they might have done that. I don’t think so but I won’t assume in this case.
If the low/reverse drum is very loose and burned up, that trans may have a failed roller clutch in it.i would inspects the entire back end of the case, and the output support for damage
 
Yeah....you're right. My terminology could have been better in describing that.

The output support is damaged. It's not dug in considerably, but it is not smooth. It also doesn't look the same as the 904.

It is the low reverse drum that has the play. I should have assessed it better before posting.
When I have some time I'll take a close look at it. I'm pretty sure with both transmissions here and apart I should be able to correct any problems I find.

I still haven't gone into or studied the valve body entirely yet so I'll look at that as well.

The problem could be there. I'll post more when I find something
 
Yeah....you're right. My terminology could have been better in describing that.

The output support is damaged. It's not dug in considerably, but it is not smooth. It also doesn't look the same as the 904.

It is the low reverse drum that has the play. I should have assessed it better before posting.
When I have some time I'll take a close look at it. I'm pretty sure with both transmissions here and apart I should be able to correct any problems I find.

I still haven't gone into or studied the valve body entirely yet so I'll look at that as well.

The problem could be there. I'll post more when I find something
Just be sure to keep the components from each tran separated from each other until you decide which one your going with.
 
View attachment 1715360963
A999 worn down....output shaft support -

View attachment 1715360964
I think the output shaft support is worn down due to the .023 play in the governor area......a new and thicker snap ring should fix this.

View attachment 1715360965
Here is the 904.....the okay here is .016.......much smaller than the one above. I forget the spec. Will post it tomorrow

The thrust washers were .049

The thick one was .125 on part of it and .122 on part of it. It has the snap ring groove run down int it
If the output support sealing ring area is scored or worn heavily you can swap that part from your 904 or any other 904 lockup or not.
I am not sure what the arrows or endplay you are referring to on the governor support. That should not be a wearing area. It appears you are pointing to snap rings and not thrust washers. The little bit of play you are referring to is normal and nothing to worry about.
 
View attachment 1715360966
This is the 904 with the reverse drum on the shaft. See how shallow this is......-

View attachment 1715360967
Now look at this....I can slide it back this far. This is what it is like in the transmission wen the stack is installed.
The 999 1/4” play is this....or identical to it. I think it’s normal. -

So.....if all this was normal......and let’s say the output shaft sealing rings were still sealing...l.which I think they were.
No clearance issues.

What would cause the reverse drum to wear like that......
Hard to tell what you are looking at. I can't see anything wrong.
Maybe you need to take a closeup pic.
 
48237868626_ced30015ea_m.jpg
Here is he 904......the band surface area is higher than the
Un-machined area. This drum is good....no hot spots. -


48237868621_966bb2e003_m.jpg
Another picture of the 904 reverse drum -


And here we have the 999 reverse drum. The un-machined part is higher than the band surface area.
I doubt it came this way. I think it’s seriously worn down.

48237954287_5f907de69f_m.jpg
999.....you can see how far down it is.
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What would cause the 999 reverse drum to wear this badly.

Also.....aside from this..
I cannot see where any of the metal in that filter came from or why the fluid is so black....which I’m guessin*is metal wear. The magnet was saturated
 
48237989207_8a558e1715_m.jpg
here it is pulled forward.


48237904221_e572362b34_m.jpg
Here it is.....slid back-


This is causing the reverse drum movement I was talking about.
It’s not quite 1/4” but it’s a lot.

It moved like this when the trans was assembled in the 999.
I didn’t check it in the 904 assembled

This picture is of the 904.

I think he reverse drum is allowed to move back and forth like this. But I can’t say it’s fact as I didn’t check the 904 before taking it apart like I did the 999


Also......with a 3.8 kick down and the larger band
A double wrap reverse band.
87 transmission.
I need to be sure of the adjustment specs on both of these. I’ve seen several different ones. Might be why the reverse band did what it did. Could have been set for an earlier 904 or something. Like 2 turns out instead of 4 or 5 or whatever it is.....and they set it too tight. So it wore down the reverse drum
 
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