Inspection of a 904 torqueflite

-
glhx said:
When I measured the gear train end play. I put the gear train together with the appropriate snap ring. THen held it upside down and measured the gap between the rear ring gear and the output shaft.
With the .087 snap ring I got not even .008 clearance. My feeler gauge set wouldn’t go smaller than that. So I put the .065 ring in and got .030

There might be .001 or .002 variation in there but I can see that with the .085 snap ring it’s too tight.

The torque specs on the bands.
They didn’t match up. I tightened Dow the rear band to 72 inch pounds and then backed off the required number of turns. The band was still tight when done to spec. It took another 1/2 to get it to move.

So when I went to tighten down the kickdown band. There was no socket I had that fit the adjustment bolt. So I looked online at some of the people on here and did it by how it turned.

Tighten it down....loosen it till it just turns and then back out 1/2 turn.

The clutch pack was air checked at one point. I don’t remember the spec. This was also done with no fluid soaked into them like it had now.

My air compressor took a dive so I have not been able to apply test them after putting it together the second time.

When testing total end play. I put a dial indicator on the input shaft and move it back and forth by hand.
It’s hard to even get an accurate reading because the trans is so tight. I can see that it’s close to 10-15 thousandths. This is with the bands adjusted loose to allow max end play with no resistance.

The transmission turns fine with the torque converter and a pair of pliers but is pretty hard to turn by hand....and it would be because all that’s in it is transgoo and some fluid mixed in.

I’m on the fence on whether it’s ok or not. It’s my first one and I’ve never seen a new transmission or a rebuilt one.

The 904 turned out the same way....but it would because I built them the same.

The 700r4 I have seems more what I see as normal....but it’s worn in. The other 700 I have is tight and looks like it has a new pump so I know someone had been in there.....but the fluid smells burned.
I’ve been buying parts for that one for a rebuilt to try to make it last longer and research to set the tv correctly....but that’s another story.
Click to expand...
Is the rear band a double wrap style, if it is how many turns are you backing it out. You do remember that it will only rotate one way because of the roller clutch. I beleive the double wrap band calls for four turns out. Front band would be 2- 2 1/2. First time you drive that thing it will all loosen up, that's why I say do not go by feel.
Adjust the band by the book and do indeed post your clutch pack clearances, especially the rear one.
 
How do you guys torque the kickdown band down.

The reverse band is a double wrap and I can torque that down with a socket head that works. I’ll try to do that today and see where it sits. I remember doing it correctly and the transmission wouldn’t even move.....it was torqued to 72 inch pounds and then backed out 4 turns. I went by the atsg spec so it must have been 4 1/2 to get it to finally loosen up. I just thought.....this doesn’t seem right.
It this supposed to feel locked or dragging?
I do remember seeing it to spec and the trans was locked up

The kick down couldn’t have a standard socket on it....the bolts have rounded sides.
What I am going to try is a crows foot open end or better yet.....an 8 point socket if I can find one.....to torque it down.
the special tool for the reverse band c-3705 is like $60 and then gets a 5/16 socket on the end of that......if I did this all the time it would be worth it but not just for two transmissions. I’ve seen pictures showing that adapter making it easier to do in the car.
I think I tried adjusting the bands before in the car. The kick down seemed like it was almost impossible as it was buried. I see now that this adapter would have helped.

The reverse was done turning the outputshaft one way and the kick down was turning it the other way. The sprag is locking it in one direction.

Everything I’ve down so far except for the bands and the second rebuild of the clutch packs without using air to compress them was done pretty carefully.

I have to get a new compressor anyway.
 
Another question is the speedometer seal. I’ve always used a regular seal with a little clip.

With some of the parts I got. It came with the metal spring clad seal. It fits into the bore very tight. I didn’t put it all the way down. It’s still sitting on the surface.

I think it’s the wrong seal but I see eBay selling speedometer gear housings with this.

49133247786_199987915f_m.jpg

Original seal


49133437087_7771da3e7e.jpg

This one comes with both.

I only have the spring clad but I don’t think I want to use it. The older style worked fine.
 
glhx said:
How do you guys torque the kickdown band down.

The reverse band is a double wrap and I can torque that down with a socket head that works. I’ll try to do that today and see where it sits. I remember doing it correctly and the transmission wouldn’t even move.....it was torqued to 72 inch pounds and then backed out 4 turns. I went by the atsg spec so it must have been 4 1/2 to get it to finally loosen up. I just thought.....this doesn’t seem right.
It this supposed to feel locked or dragging?
I do remember seeing it to spec and the trans was locked up

The kick down couldn’t have a standard socket on it....the bolts have rounded sides.
What I am going to try is a crows foot open end or better yet.....an 8 point socket if I can find one.....to torque it down.
the special tool for the reverse band c-3705 is like $60 and then gets a 5/16 socket on the end of that......if I did this all the time it would be worth it but not just for two transmissions. I’ve seen pictures showing that adapter making it easier to do in the car.
I think I tried adjusting the bands before in the car. The kick down seemed like it was almost impossible as it was buried. I see now that this adapter would have helped.

The reverse was done turning the outputshaft one way and the kick down was turning it the other way. The sprag is locking it in one direction.

Everything I’ve down so far except for the bands and the second rebuild of the clutch packs without using air to compress them was done pretty carefully.

I have to get a new compressor anyway.
Click to expand...
When you adjust the rear band, do not try to rotate any shafts. Try to grab hold of the reverse drum itself and try to rotate it. Remember it should only turn one way. Trying to rotate the output shaft is going through the planetaries. You will get a false feel.
I have seen guys adjust by the amount of servo travel. Something tells me 1/4 inch travel
 
I had it all put together and after all the advice from you guys. I decided I needed to be a little more patient with it.

I made some pump guide pins from cutting off bolt heads. Then tapered them and rounded them for better pump installation. I was able to line the pump up and get the gasket right without them but it was not a user friendly ordeal. Now the gasket and pump slide right on and are ready to be bolted in.
These pins help in a big way and to me are really a necessary tool to have.
49139253308_b4ee5bf7d7_m.jpg


Then when the pump was on.....I remember how hard it was to get out. I picked up a pump puller for that. Some tool that grabs below the splines and catches them while pressing on he input shaft. My pump has trans fluid on the seal so it should come right out with ease. They said this puller would work with a 727, 904, and all the GM transmissions.
49139773841_3864a66fb5_m.jpg


I didn’t have any 8 point sockets......so I had to get a small set of those to torque down the band adjusters correctly.
49139757321_ab7d93501e_m.jpg


I don’t know what’s up with that reverse band and why it had to come out so far except that I was using the output shaft and it went through the planetary. If I torque it to spec it should be good no matter what I think and then I’ll have a good frame of reference with how far we lift the apply. Pretty sure right now it’s wrong.

So now all of this will be a little more user friendly to do right. I got in a bit of a hurry with it. Then sat down and remembered all the study and work that went into doing his right....just to get in a hurry at the end and maybe miss something. It’s winter so it’s not like it’s going anywhere.

So I’m going to take it back down and measure the packs again. Get an air compressor and check them after compressing them.
Then torque the bands to spec the correct way and see what I come up with.
1/4 on the kick down and 1/2 on the reverse

I mean.....I need the right tools to get this right. I will also need them for the 700r4 I’m doing next.....which I might as well call it a 700....Sonnax...4 as it seems to need a lot of upgrades. Not that this is a mopar trans.....I have a lot of respect for the mopar transmission of the 904/727 family after looking at the Chevy stuff and how complicated it is and the level of Or lack quality gm put into it.
 
Last edited:
You don't need some fancy pump puller. Just pry between the sun gear shell lugs with a screwdriver. If that doesn't do it, then screw two 3/8" bolts into the pump and use a 90 degree angled pry bar; like a small demolition bar against the inside of the bellhousing.
 
49165727443_ea51e7879b_z.jpg
-

49165727453_3fec43cebf_z.jpg
-

The forward clutch pack is .072 and was taken on the high part of the waved snap ring.
The spec is .032 to .055
I did not air check it as I still don’t have a compressor.

49165727438_098a63c816_z.jpg
-
This is the 5 clutch direct. The spec is .096 and is within he spec of
.075-.152
It has a straight snap ring.
 
glhx said:
I had it all put together and after all the advice from you guys. I decided I needed to be a little more patient with it.

I made some pump guide pins from cutting off bolt heads. Then tapered them and rounded them for better pump installation. I was able to line the pump up and get the gasket right without them but it was not a user friendly ordeal. Now the gasket and pump slide right on and are ready to be bolted in.
These pins help in a big way and to me are really a necessary tool to have.
View attachment 1715429996

Then when the pump was on.....I remember how hard it was to get out. I picked up a pump puller for that. Some tool that grabs below the splines and catches them while pressing on he input shaft. My pump has trans fluid on the seal so it should come right out with ease. They said this puller would work with a 727, 904, and all the GM transmissions.
View attachment 1715430000

I didn’t have any 8 point sockets......so I had to get a small set of those to torque down the band adjusters correctly.
View attachment 1715429999

I don’t know what’s up with that reverse band and why it had to come out so far except that I was using the output shaft and it went through the planetary. If I torque it to spec it should be good no matter what I think and then I’ll have a good frame of reference with how far we lift the apply. Pretty sure right now it’s wrong.

So now all of this will be a little more user friendly to do right. I got in a bit of a hurry with it. Then sat down and remembered all the study and work that went into doing his right....just to get in a hurry at the end and maybe miss something. It’s winter so it’s not like it’s going anywhere.

So I’m going to take it back down and measure the packs again. Get an air compressor and check them after compressing them.
Then torque the bands to spec the correct way and see what I come up with.
1/4 on the kick down and 1/2 on the reverse

I mean.....I need the right tools to get this right. I will also need them for the 700r4 I’m doing next.....which I might as well call it a 700....Sonnax...4 as it seems to need a lot of upgrades. Not that this is a mopar trans.....I have a lot of respect for the mopar transmission of the 904/727 family after looking at the Chevy stuff and how complicated it is and the level of Or lack quality gm put into it.
Click to expand...
If your pulling it all apart I'd remove and grind the kickdown band adjuster end into a 5/16 hex and be done with it, no special sockets needed. Just an idea if you're feeling adventurous!
 
Between the two transmissions. That’s the one thing I did mix up was the retaining rings.

I can pull the other one back apart and check the sizes of those or I can just order some rings that will close the gap. The .75 or the .85 should bring the forward clutch to mid .040 and the other one at .096 I guess should be fine as long as it’s in spec.

The reason I mixed them up was to put the flat ring on the 999. Either way.....I assumed....that the wavy ones were all the same and that the clutch packs all had the same size frictions and steels so I figured it wouldn’t be a problem.

Realistically and atsg manual aside. Where do I want these specs to be and is tighter, better?

If I’m going to order snap rings I might as well get this where it needs to be and get the tolerances for the best performance. Is atsg spec what I need to follow?

On the 1/4” on the kickdown and 1/2 on the reverse. That’s how far I can lift the servo lever.
 
Last edited:
12many said:
If your pulling it all apart I'd remove and grind the kickdown band adjuster end into a 5/16 hex and be done with it, no special sockets needed. Just an idea if you're feeling adventurous!
Click to expand...

Wish I’d thought of that. I did get the 8 point sockets for it. Have to get the end play and clutch packs right and then I’ll focus on the bands. Thank you for the cool idea.

All I know to do for the servos is tighten them to spec and loosen them. I don’t really kno the resistance or the feel of he bands without a frame of reference.
 
Last edited:
That 1/4" and 1/2" travel really is of no value on band adjustment. (Had to edit post as I believe I misunderstood your post:eek:)
 
Last edited:
I pull every band lever to check it. But I also air check every clutch pack to double check the clearance there as well. It's a good habit. Clutch clearance on the slim side will last longer.
 
I took the other one apart. It has two wave rings at .045

This wouldn’t give me anything on the closer side.

I’m thinking a flat snap ring on the forward clutches of .076 or .085
Giving me .41 or .32

On the direct clutch.....the one in there is .062
If I run the .076
I can get a clearance of .082

Would tighter be better these.....than the specs I’m shooting for.
 
.32 is too tight. I'm not so sure a flat gauge will give a correct measurement on a waved ring. I use a wire. Are you saying that one pack with a waved ring only measured .045 to the top of the wave?
 
CudaFactHackJob said:
.32 is too tight. I'm not so sure a flat gauge will give a correct measurement on a waved ring. I use a wire. Are you saying that one pack with a waved ring only measured .045 to the top of the wave?
Click to expand...

No. The .045 is the thickness of the metal. I was guessing that when the clutch was applied. The wave became straight. So I measured the metal thickness as if it was straight. I’m not really sure if it flattens out.

I can throw the straight one in there and use that for a better guide. I’ll do that. I don’t really want the wave rings in there anyway.
 
I put the straight .062 snap ring in the forward clutch. It gives me
.063 clearance.

Still not spec.

The .076 ring would give me .049
The .085 ring would give me .040

Which one would be best?

The clutches and steels are new and I measured all of them. They are factory spec
 
You must log in or register to reply here.
-

Back
Top