Inspection of a 904 torqueflite

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Washers showing copper is normal. They start out gray; no copper showing. Have you checked the direct drum inside where the rings ride or are you too busy wondering about converting a 904 into an overdrive?
 
There was something of an overdrive 904 with lock up known as the A-500 loosely based on the A999 torqueflite (HD904 with extra clutch discs and lower gear sets). Used in the nineties in Dakotas and the like. There are articles here on forum about adapting one into an a body and U.S. car tool carries a crossmember if You don’t want to modify your existing unit. That is if you really want to get into the overdrive deal. A 200R4 lockup GM transmission seems to be a more popular option, but I have yet to research the topic thoroughly enough to know why.
 
I think I have checked the inside of the drum.

If what your talking about is the vertical motion where the piston pushes the rings up with pressure and they come back down to disengage. Those spots in both drums are in good shape.

No scoring at all.
 
There are steel rings on the back of the pump that correspond with the inside of the direct drum. Often they dig into the drum; necessitating replacement.
 
I see what you mean now.

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When I drag a fingernail across them. All they do is go smooth.
It doesn’t seem like they dug in at all. I found some pictures of what you mean as well. These don’t look like they are damaged in any way

From what I can tell the planets and the sun gear, torque converter and bushing have taken the most damage.
Also.....that ring gear on the clutch spline side is worn just on the bottom part.
The helical gear on the other side.....no damage at all

I’m also wondering about that output shaft support.

I’ve looked on eBay for some used parts. Found sets of them for sale for reasonable. I do not know if they will fit what I have.....and I mean as a set. If I go to a smaller sun gear with matching shell and planets as a set. Will the newer transmission parts fit into my older case. The one in the picture of the set for sale that show it to be a lower gear set. That doesn’t matter to me. I just want good parts that fit.

There is no pitting in any of the parts. Just the crowns ground down some. What ever did that didn’t touch the planets matching ring gear.

Another question. This forward set has the waffle textured friction plates. Was that standard? The direct drum has smooth textured frictions.

This transmission didn’t make a sound. Shifted perfect and smooth before I took it out.
 
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The friction patterns you describe are backwards. Waffled in direct and smooth except for maybe very small grooves in forward.
 
Yeah. I had them backwards. not in the drum though. I left everything where it goes so not to lose track of things

Having a hard time finding a planet and sun gear new as well.
Unless the stepped shell will work. I doubt it however

They have no up and down play at all. They are snug in there but freely moving. They have side to side play however which I think is normal
 
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Idk what up and down and side to side even means. Or snug or normal either. I understand thousandths. The front planets looked ragged to me but not sure. Probably just needs new fibers and front band and thicker thrust washers.
 
The rear planets are running .013
The front planets are .018
Side clearance.

Even all the way around. None of the pinions with more side clearance than the other.
The only way I can measure any of the other play like radial is with a dial indicator and I don’t have one of those yet. Soon....

If I grab the pinion and radial I can push/pull on it I feel no play....not enough where it’s going to be a problem.
 
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grab each planetary with thumb and forefinger and see if you can wobble them. If not, I think it's time to take apart the pump. Make sure you don't flip the pump gears over.
 
No wobble at all on any of the planets.

This is the pump and stator. A question is.....do you replace these rings that go into the direct drum. Can they be reused. What kit should I get?
The lockin*tabs seem to be straight sided and not beat up by the converter.

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First side tab

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The bottom of this shaft is dark blue. Looks like some heat discoloration here. Might come like that. Doubt it. I’d say the converter did this but I don’t know.

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This is the other side locking tab-

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Flickr didn’t want to make this bigger. I marked this before doing anything at all. The clearance around the side seems fine. No measurements have been made. -
 
Yeah. The cracked torque converter hub basically took it out.

One thing also is that this car ran with no kick down for a while. Maybe a few hundred miles or so. Could explain why the clutches were so shot. It was done before I knew that torqueflites had to have one of those to not destroy themselves. When I got the engine and trans it wasn’t there. Took a while to find the correct 4 barrel parts to make it right. It’s also just a 43 year old transmission and it’s just time to give it some life back.

I’ve seen where they put a500 clutch drum in there and it fits fine but I couldn’t find a lot on it and figured it lasted this long with 4 that it would be fine.

What I’m thinking is to get a kit from Oregon performance, or get parts separately that have a good reputation on here, like Raybestos or borg Warner clutch frictions. I think they are .086

Possibly some steels since there was a burn mark on one of them.

Have the kick down band relined
A thrust washer kit.
Babbitt front pump bushing
Tail shaft bushing
All new Gaskets and seals
Perfect circle rings

A tf1 or 2 shift kit. I dont drive it hard so a tf1 would probably be fine. I just want it to hit a little harder and not wear as well as take care of the other problems the 904 comes with...They said something about 2-3 overlap

See if I can find all the end play specs. Never done anything like this. I have seen washers throughout and want to know how to place them or put new ones in to take up the slack and where they go.

I think I’m gonna leave the gear set in and just be easy in it. New fluid and seals with good maintenance should help it live as long as I need it to and they are not really hard to remove if it became a problem. I’m just glad I’m aware of the condition of them and the rest of what the inside looks like

Thoughts on this plan?
 
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Why make it so complicated? Throw a cheap overhaul kit in it and a pump bushing and call it done. A band off ebay for $15 free shipping. Don't replace the tail bushing. Whatever rings are in the cheapo overhaul kit. No thrust washer kit; just shim the selectives to take down the endplay. Stake the pump bushing. You talk overkill on meaningless parts but won't post more pics of the planetaries. Forward frictions are not .086. That's just more meaningless info. Do you really think the cheap kits are bad? There are no bad kits out there. You want to ignore the planetaries but talk about an A500 drum? You already took this trans way too far apart. With that and the way you're talking about parts, I worry that this will not go back together right and work properly.
 
I haven’t been able to find a good planet set yet. I’ve looked at several places and still am looking for one I know is good. I want to replace it. I’ve even looked at grinding the planets off and replacing them. I’ve looked at countless pictures of them and what they are supposed to look like. I’ve even seen people selling the online in the same shape as mine saying they are good, but I don’t know and if I don’t know then I can’t discern whether to use what I have and it last 30-50k or if it will last 5k and I should have fixed them.

The sets I’ve seen are for newer 904 and I don’t know if they will work with what I have. They have the stepped sun shell. The information on what fits and what doesn’t is all over the place. Some say yes and some say no. Some say they need a 5 disc drum.

Some say in order to run a 5 clutch you need a pump that is cut down. Some say it drops right in with the existing and with so many saying this and that. I just done know. If I can get a better clutch drum for $20 and add another friction even with the parts I have now....it’s just not that much added cost.....but that’s IF it works and I don’t know and there’s not a lot on it. I’ve seen a guy do 5 discs in a drum and the 5th disc just slipped. So I’m like....how does his slip and the other doesn’t.....Transmission are just one of those things people don’t mess with.

Some say the clutch packs are 4/3......and I get in there and see 4/4....so I get caught up in what I’m reading vs what I’m seeing and I’m like damnit.....has someone been inside this thing before adding clutches.....then only to find out that 75-78 they had 4/4 and then I find out there is a 999 and a 998. I’m lost in all the information

This is the first time I’ve done this. I know I sound all over the place, but I promise you the detailed information is where I work best at. It sounds like I over complicate it....and I do sort of.....but it means I’m weighing options and those options do make sense.

Do I go all out or do I put it together and run it. Part of that is based on future plans. I’ve got a turbo 350 blown here as well. Is it worth it to buy a bushing installer for $70 when I know I will need it in the future because that trans is blown and I know the frictions are completely gone. Then I question whether I even need a bushing installer and wonder if my cam bearing installer will work as it really does the same thing. If it will put a bearing in a cast iron block. Surely it wouldn’t have problems with aluminum.

All these little corrections everyone has been doing on here has made a difference. Like saying the waffles are in the forward drum instead of the direct drum and even calling those by the wrong name. I won’t get it wrong twice.

When this transmission goes back in......and I hope I don’t eat my words on this. It will work. Nothing will be missing. The clearances will be in spec and I will have a fairly complete understanding on how it operates and what makes what happen. The second time I do it......there won’t be questions.

But I have to sort through all the information.

I can post many pictures of the gear set. Detailed pictures.

I thank you for being patient with me and even answering anything. It means a lot.
 
This is looking like a very good candidate for rebuild. Clutch frictions, front band, pump bushing and go. I'd even reuse the filter and fluid. Idk what the endplay measured before it came apart, but pick up a thick selective washer that fits onto the front of the output shaft.. It's about the size of a quarter.
 
I will reuse the old fluid. It had about 30 miles on it.

What you can do to get rid of contaminates in fluids like trans or oil, even coolant is Go to the local paint store and get the cup filters for free. They have stacks of them. I actually do a pretty nice paint job, but to look at my car you wouldn’t know it.

What I do is use 1,2 or even 3 of these paper cup filters. They strain very fine particles out of paint. So when you start stacking them, you can get the smallest dust out of used fluids. A trick I learned to help with that problem, that works very well.
 
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When I get the stack cleaned up. I’ll put it back in and check to see what the original end play was. Can go from that.

I’ll go ahead and start ordering some parts to get this and the engine that’s torn down back together and get this thing back on the road.

The contaminates in that filter are from where I took down the valve body to change the shifter shaft seal. I tried very hard to keep it as clean as I could but there was no way under the car to get it all. The filter did its job that’s for sure.
 
glhx said:
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Haven’t taken out the front servo yet. I’m sure there is some black funk in there as this seems to be a place where the fluid doesn’t cycle as much. The back servo had very little of this though, so maybe this one won’t-

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The output shaft rides in this piece. There is a wear pattern on the aluminum. Is it worn out? I don’t know -

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This is a tail shaft bushing. It looks steel. It has some wear patterns and looks eaten up in some places -

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What the fluid looks like with friction material in it. This was in the bottom of the pan-

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Another of the tail shaft bushing-

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accumulator housing.....do these wear?

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This bolts to the back of the main transmission housing. It has wear patterns. There is a picture of it above as well. It’s all aluminum. Do these typically get replaced?-

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Main housing. That’s where the overrunning clutch goes. There are large needle bearings and springs. I’ve seen where people replace the springs and bearings but leave this part in there?-

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Valve body......black coating is friction material fluid that leaked out when I turned it upside down-

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Rear servo arm pin....housing. The pin that holds the servo goes here, there is a wear pattern -

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The pin had black film on it-

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Rear servo piston-

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This is the forward clutch drum before I took it apart. There is wear on the bushing.....but I don’t know if we replace these when they are like this or not. The clearance is shown between the clutch packs and the snap ring. I’ve heard this is measured with a feeler gauge. I need to know about this-

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This pin is for the rear servo arm. That o ring leaks and goes out the tail shaft seam. It’s rare the or ring leaks but I’ve heard when it does it’s hard to track down and the tail shaft has to come put.
You screw a bolt into the back of this pin to get it out. It slides right out and the tail shaft is what hold it in there-



That’s all I have for this. I have not taken apart the front pump yet so I don’t know what that looks like. I know the bushing that the converter rides on it eaten up but that was brim a cracked torque converter hub which is common with these 904 transmissions.

I could have just pulled the pump and put a new bushing in there and maybe gotten some Mike out of it. I figured the transmission was not far behind and I didn’t know what had ever been done to it.
I can say that it was painted ford blue so it has been out of the car.
I can’t say if it was even original to the car. It was out of a 318 76 charger.

I won’t be driving this car much. I don’t really drive the car hard at all and don’t need performance parts. Maybe a shift kit.
Click to expand...

I see very little wrong in those pics. To my eyes that trans just needs a freshening with new clutches and new bushings.
glhx said:
I just tore down this 904

I’d like to know what kit to buy or what separate parts are needed to refresh this or whatever it needs.

It had no problems shifting before I tore it down. I had recently changed the fluid. There was a lot of black powder in the pan when I pulled it to do the change....
So this time there was very little. It was probably run 50 miles since the change. I tore it down because the torque converter hub was cracked and tore up the bushing it rides on.
I figured if that was bad....what else was bad.

This is the first time I’ve ever taken apart and transmission. I have a general idea of how it works. Some of the forward clutches looks like they were pretty rough compared to what they should look like.

It looks like I was about to lose all my forward gears

I’ve got about 50 pictures I’m going to post of the wear on these parts.

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Reverse band.....I don’t even know what this is supposed to look like. Are there any upgrades for this. It doesn’t look as worn as the other band -

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Don’t know what this is. It has a thin bushing in it. Should I replace the bushing. It also looks like something sits or turns where it’s shiny -

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The reverse clutch packs didn’t have the gouges taken out of them like the forward clutch pack did. This one just has this one spot where it’s gray. That’s gouged in a small place but I’m sure it gets worse after they get beat up like that -

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Looks ok. Doesn’t mean it’s good. This is one of the reverse steels. How can you tell if these are good and can be kept. Or bad and need to be replaced?-

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A typical example of the reverse clutch. This one is intact -

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a picture of the output shaft,......-

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One of the reverse steels......the one has the wear marks on it. Those round line Pattern like it needs to be polished -

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Another reverse clutch pack. Looks a little worn....you can see where it has penetrated the surface and gotten a little rough in places -

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Looks like the reverse Simpson gear set. What are all the gouge marks from. All the rough texture inside there. The gears felt fine. They seem tight and don’t have a loose feel by hand to them. -

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A picture of the upper end of the output shaft. Those two polished parts ride on the copper color bushings that are pressed in to the clutch packs or other parts like them-

I left out pictures of the other steels and reverse clutch packs. They look the same as the ones above. No burn marks on them. Very little gouging or friction surface broken down.
The forward gears are nothing like this. Much worse.

All that black stuff I found in the pan before this trans fluid change was friction material.
I changed it because it was leaking badly. The seal on the area where the valve body comes out of the transmission to shift it......went bad. I had to pull the valve body to replace it. As I didn’t drive it much.....it didn’t have time to keep trashing the friction material. It would have with more miles and I would have had more in there until losing all forward gears. I just had a turbo 350 lose all forward gears like this. I’m guessing this is exactly what happened to it
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i see very little wrong in there. The bluish colour on what your are calling the input shaft is normal from the factory.
The marks you are looking at on the Simpson gear sets are nothing to worry about. Those surfaces do not touch anything. You need to look at the shiny surfaces in between the teeth. As long as there's no scoring in there and the gear is not sloppy on the pin I would reuse it.
That trans just needs a freshening. All the parts that have a copper colored bushing and the tail shaft, bring them to a trans shop and have them change the bushing.
Buy any standard rebuild kit and install new clutches, and seals.
Double check your clearances to see that they are in spec and run it.
Very little wrong from what I can see. Imho
 
The end play is .055
If you pull the input shaft in tight it goes to .059......that’s with the tail shaft still off the transmission.

When I put the tail shaft housing back on I get .051

This is with the transmission just bolted back together and snugged down.

I’m going to measure all the thrust washers and shims as well as the gap for both clutches to see how worn they are.
 
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