Yet another 904 rebuild thread, what kit?

-
72bluNblu

72bluNblu

FABO Gold Member
FABO Gold Member
Joined
Nov 28, 2008
Messages
15,054
Reaction score
9,112
Location
NorCal
Ok, so yes, I've seen a bunch of threads on 904 rebuilds. Most are super helpful, but I'm not building a monster engine so I kinda think most of the suggestions in the threads I've read on building bulletproof 904's will be totally overkill for my application. With that in mind, this is for the 904 that's going behind a 318 in my '71 Dart GT.

318 is .025" over, forged flattop JE pistons, RHS X-heads with 1.92/1.60" valves, Lunati 60403 cam- advertised duration 268/276, lift w/ 1.5 rockers .494/.513". Edelbrock air gap intake, holley 670 street avenger, Doug's headers, dual 2.5" exhaust. Static compression calculates at 9.662:1, DCR is 8.265:1. Should be fun, but I think it's a pretty safe bet it won't make any more than 325 hp or so.

The 904 is the original transmission, it shifted fine the few times I drove the car before I tore down the engine. ~84k miles. I haven't torn it apart yet, but there wasn't any giant chunks of friction material in the oil so it shouldn't be completely awful in there. It's going to get a new converter, the cam specs call for a 2400 stall. I have a Transgo TF-2 kit for it and the Mopar Performance +1 qt steel pan with a drain.

I was looking at this kit and adding on a reverse band, seems pretty complete.
Dodge A904 904 Transmission Deluxe Rebuild Kit TF-6 TF6 60-71 | eBay
Just standard stuff, high energy plates and steels, standard kickdown and reverse bands.

Figuring that I have an engine that will only be a bit over 300hp, I'm thinking all of that should be fine? Don't really think I'm in a performance spot where I'll need red plates, kolene steels, kevlar bands, etc. Just a street car, not a drag racer. I like some spirited driving but nothing too crazy, and I'm sure most of you know by now I'm more of a corners guy anyway. The Dart is numbers matching for all the major parts though and I need an "easy" car to drive so I'm keeping the auto in this one, power steering, factory A/C, that sort of thing. Just want to freshen it up, firm up the shifts, and keep it running smooth for a long time.

So, what say you? That kit, the TF-2 and extra quart pan? Anything else? Or is my thinking off?

Thanks!
 
Nobody builds 904's for warmed over 318's? I don't really care either way, the red plates, kolenes and kevlars aren't insanely priced. But overkill isn't always a good thing, especially when friction surfaces are involved...

@fishy68?
 
You seem to know everything. No sense in giving you any suggestions.
Sorry I even tried. Lesson definitely learned.
Good luck with your trans.
 
Last edited:
Better ask J Par...he's the resident 904 guru.
 
Last edited:
As far as the converter goes...I really don't know. Just pick out one I guess. Again, ask J Par. He might sell his now that he gave up and is going back to a 4-speed.
 
Last edited:
To the op, yes I think the extra clutch or the extra strong friction would make a better hold under severe racing conditions or under severe torque or power but really not going to help anything in the lower range.
We have a couple transmission supply houses here in town so it makes it nice but I would recommend if you have some place close by to do that as if parts aren't correct like mine weren't you can simply drive down and dig through their old stuff like I had to do. Also with what you're talking about and no real dragstrip time to talk about the stock rebuild kit with a nice trans go 2 shift kit will make you plenty happy for a long time. And also when you pull this apart and see how utterly simple it is and your intelligence has been insulted by how simple it was you'll figure that in five to ten years if you had to do it again you'll probably be doing it in your sleep.
I'll just stand behind this one comment I was a little pissed that someone called me out on your thread sorry about that
 
Last edited:
I build my own 904 for bracket racing..I use stock discs and steels....A stock rebuilt kit will would just fine...get everything cleaned...check your clearance on your clutch pacs...

They are so simple the guy post above mine could do...

Transtar Super Deluxe Overhaul Kit for Chrysler TF6 (A904) 60-Up from Northern Auto Parts

I have a great video that walks you thru the rebuilding of a 727...and the 904 is very similar in design....It is free...just send me your email address and I will send you a link for the download...it is 4.7 gb so dont have dial up...
 
TylerW said:
I can share what I did on mine:

I used a PRK1200D-S kit from Portland Transmission which I obtained via eBay. it's a nice kit with pretty much everything in your kit you have linked to, BUT, mine used Raybestos standard-type frictions. This was my first rebuild and I did a lot of research before buying a kit. I discarded the idea of red alto frictions, kolenes, etc etc after it ebcame clear that they are THINNER than OEM-style frictions and steels in order to fit more of each in the clutch housing.

The only problem with that idea is they can't absorb heat from slippage as well as the original-style stuff, so I said nope. Past that, I had my original cast iron front band relined(technically I exchanged it for one already done). I threw the "new and not improved" flex-style band that came with the kit in the garbage and suggest you do the same. Hold one beside the other and you'll see how much better the original is. I re-used the original low-reverse band, it was fine and gets little wear.

I replaced the front bushing even though mine was fine. I did not replace any others because not only does the kit not come with them but they were also in very good condition. The thrust washers were all fine but measure them to make sure. Clean clean clean. Don't forget the washers on the pump bolts. Make sure the halves of the pump are aligned or you'll never get it back in the case.

I also used the TF-2 and somehow got it installed DESPITE using the instructions. I don't know if the people that have written and revised those instructions over the years have gotten bored with it and decided to mix in some challenges into it, but those instructions are terrible. Several steps give you three or 4 options without ANY explanation what the result of each choice would be, outside of some silly references to coffee-spilling or whatever.

I read several TF-2 install threads and they all said the same thing...if you want a transmission that you can even stand to drive, go conservative on every choice. You can ALWAYS go back later and drill holes larger, etc but if you go too aggressive in the beginning you will have to do it over with another VB. I left the factory 3.8 ratio kickdown lever in place. I did the accumulator mod in the TF-2 kit along with the most conservative line pressure mods.

The end result is that I have a sweet-shifting trans. It goes in gear right now, shifts right now but is not harsh. The line pressure mods make it very picky about throttle-pressure settings. I had to back my adjustment off looser than it was or it wouldn't get out of 2nd gear. I used the Factory Service manual for my year, worked well.

Hope this helps. That other guy got 315 replies and never even finished it to my knowledge. Good luck man.
Click to expand...

Above are some wise words. For 300HP or so, this type of build for a street car is right on the money. About the only thing I'd do is ask for "waffle lined" frictions, rather than smooth or radial lined frictions, or perhaps consider the high energy frictions used in the A500. Many builders I dealt with, would use the high energy A500 frictions for a commercial vehicle or someone who was towing a trailer. Again, your choice. Stay away from the TF-3 kit, it's not what you need for a street driven car, the TF-2 is more than enough for what you are looking for. If you have an issue with the installation of the kit, phone Transgo on their tech line. Some guys like the TF-3 for the street, but other than the "fun" of constantly shifting I can't see any advantage over it to the TF-2. Might be a good idea to find out if the techs at Transgo recommend the TF-3 for a daily driver.
If the front band in your transmission is a flex one, you may have problems getting the cast band, as the band reliners need your core. The company I worked for always insisted on those bands, core in first.
Have fun, and remember DO IT RIGHT "ONCE"
 
j par said:
This is the guy with the 315 post which is actually 316 post but if you look at number 315 it will direct you to a thread I have on the Race forum where I've already driven that car several times with my wife drag raced it and drove it back home successfully videos timeslips the whole nine yards. Of course this is after being inspired by your video but there's a lot of things that you are hypocritical about especially the way you talk about people on forums like this and then you go doing the same things yourself. You should ask your Uncle Phil about that. In my opinion sometimes it's not that your dog next door that needs medicated its you!
I put a transgo stage 3 shift kit full manual in mine and it works like a charm. I used everything else stock. I also use Portland Transmission for the kit as under your suggestion and there was no less than three trips on top of it to go down there for parts that weren't correct in the kit. Thank goodness I live here in Portland OR that would have been a complete nightmare as it was it was a lot of driving. If you live here in Portland OR next to them I would go to them because if other people didn't have the parts in there correctly you have to mail back and forth. The tail housing seal was definitely the wrong one it didn't fit nothing close. They shorted me one friction disc and the inner seal for the first reverse drum was wrong. When I asked them about the lack of friction dish their answer was that they had to make the kits as cheap as possible to compete with the others out there on the internet. I use that kickdown band the kit and had no problem at the drag strip!
Again I watched all your videos right up to or you got frustrated and didn't start putting it back together or did you ever make any more videos putting that transmission back together and showing it working?. If not that's okay because if you look at any of my threads I did videos at the drag strip. I'm already tired of that automatic transmission no matter how great it works and want to put my four speed back in.
Click to expand...

I know who you are, you don't have to remind everyone. I didn't continue following your other thread because you invested all these people's help in the original thread and the least you could do was conclude it THERE and say it worked or blew up. But, that's just my hypocritical opinion.

So you've already snowflaked on the automatic and on a whim decided to put the 4-speed back in...ok. Anyway, if it is so simple to rebuild an A904(which it is) how come you stretched it out 13 pages and STILL didn't bother to conclude it there?

The flex band is still a piece of ****. You're not going be running yours long enough to see if it lasts anyway.

Yes, the transmission is built, it's in, it works great. I have a plate full of responsibilities, so unfortunately I can't dedicate as much time as I'd like to posting in threads and editing long videos. Even so, the last two videos are going to be up by tonight.

Lastly, do me a favor: don't worry about Uncle Phil(who I explained is not my uncle, you missed that part) don't worry about the dogs and most of all don't worry about me although thanks for being an attentive viewer of my channel.
 
Last edited:
transman said:
Above are some wise words. For 300HP or so, this type of build for a street car is right on the money. About the only thing I'd do is ask for "waffle lined" frictions, rather than smooth or radial lined frictions, or perhaps consider the high energy frictions used in the A500. Many builders I dealt with, would use the high energy A500 frictions for a commercial vehicle or someone who was towing a trailer. Again, your choice. Stay away from the TF-3 kit, it's not what you need for a street driven car, the TF-2 is more than enough for what you are looking for. If you have an issue with the installation of the kit, phone Transgo on their tech line. Some guys like the TF-3 for the street, but other than the "fun" of constantly shifting I can't see any advantage over it to the TF-2. Might be a good idea to find out if the techs at Transgo recommend the TF-3 for a daily driver.
If the front band in your transmission is a flex one, you may have problems getting the cast band, as the band reliners need your core. The company I worked for always insisted on those bands, core in first.
Have fun, and remember DO IT RIGHT "ONCE"
Click to expand...

Thank you sir! Yeah, I don't want a full manual auto. If I was going to do that I'd just put in an 833 and shift for real. This is a street car with a stock console shifter.

Besides maybe swapping out the frictions for the A500 pieces, is there anything else thats not in that kit I linked above that I should take care of while I'm in there besides the reverse band and the TF2 kit? Springs and rollers? Accumulator?

As for TylerW and jPar, guys, take it somewhere else. You want to pm each other nasty messages go right ahead. TylerW deleted the only post that was even relevant to my original question. I don't care who's a guru or who made a better YouTube video or which one of you is running faster at the drag strip. I just don't care. I wanted some opinions on the parts I've chosen for a pretty mild build that will probably see 99% street duty. I don't need some manual shifted bullet proof race trans that snaps u-joints backing up a 300ish hp 318. It's just dumb and unnecessary, and it'll make a lousy driver set up that way.

I asked about the red plates etc mostly to see if people think I needed them. I know they're more expensive and they'll hold more torque but that doesn't make them better for my application. That's like saying carbon-on-carbon disk brakes are the best and everything should run them. Yeah, they're spectacular for a formula-1 car. But even formula-1 cars can't get them up into their operating temperature in the rain, making them terrible for anything else.

For street use the lowest level of friction that will get the job done is usually best in my experience. More forgiving, easier to drive, and as long as the parts are up to the job they'll last just fine. Using higher performance parts that aren't necessary just makes crap more difficult to drive. I mean, if I need them I need them. If I don't, and it sounds like I don't, then they're an unnecessary expense that won't improve (and could actually worsen) my driving experience. If they're better for a reason and they're not just overkill then tell me why they'll work better for this application. I'm ok with a little overbuild but too much doesn't make for a good driver. I'm going to commute in this thing, not flog it on the drag strip.
 
Last edited:
Understandable, and I'm sorry, I'll stay with my post #8 and that's what I meant to say anyways it was just he'd comment about something I said and I didn't like his Illusions to that and then after he's done saying it here erases that he ever said it so I'm good I'm done I erased everything and again I apologize yes stage 2 shift kit not stage 3
72bluNblu said:
Thank you sir! Yeah, I don't want a full manual auto. If I was going to do that I'd just put in an 833 and shift for real. This is a street car with a stock console shifter.

Besides maybe swapping out the frictions for the A500 pieces, is there anything else thats not in that kit I linked above that I should take care of while I'm in there besides the reverse band and the TF2 kit? Springs and rollers? Accumulator?

As for TylerW and jPar, guys, take it somewhere else. You want to pm each other nasty messages go right ahead. TylerW deleted the only post that was even relevant to my original question. I don't care who's a guru or who made a better YouTube video or which one of you is running faster at the drag strip. I just don't care. I wanted some opinions on the parts I've chosen for a pretty mild build that will probably see 99% street duty. I don't need some manual shifted bullet proof race trans that snaps u-joints backing up a 300ish hp 318. It's just dumb and unnecessary, and it'll make a lousy driver set up that way.

I asked about the red plates etc mostly to see if people think I needed them. I know they're more expensive and they'll hold more torque but that doesn't make them better for my application. That's like saying carbon-on-carbon disk brakes are the best and everything should run them. Yeah, they're spectacular for a formula-1 car. But even formula-1 cars can't get them up into their operating temperature in the rain, making them terrible for anything else.

For street use the lowest level of friction that will get the job done is usually best in my experience. More forgiving, easier to drive, and as long as the parts are up to the job they'll last just fine. Using higher performance parts that aren't necessary just makes crap more difficult to drive. I mean, if I need them I need them. If I don't, and it sounds like I don't, then they're an unnecessary expense that won't improve (and could actually worsen) my driving experience. If they're better for a reason and they're not just overkill then tell me why they'll work better for this application. I'm ok with a little overbuild but too much doesn't make for a good driver. I'm going to commute in this thing, not flog it on the drag strip.
Click to expand...
 
72bluNblu said:
Thank you sir! Yeah, I don't want a full manual auto. If I was going to do that I'd just put in an 833 and shift for real. This is a street car with a stock console shifter.

Besides maybe swapping out the frictions for the A500 pieces, is there anything else thats not in that kit I linked above that I should take care of while I'm in there besides the reverse band and the TF2 kit? Springs and rollers? Accumulator?

As for TylerW and jPar, guys, take it somewhere else. You want to pm each other nasty messages go right ahead. TylerW deleted the only post that was even relevant to my original question. I don't care who's a guru or who made a better YouTube video or which one of you is running faster at the drag strip. I just don't care. I wanted some opinions on the parts I've chosen for a pretty mild build that will probably see 99% street duty. I don't need some manual shifted bullet proof race trans that snaps u-joints backing up a 300ish hp 318. It's just dumb and unnecessary, and it'll make a lousy driver set up that way.

I asked about the red plates etc mostly to see if people think I needed them. I know they're more expensive and they'll hold more torque but that doesn't make them better for my application. That's like saying carbon-on-carbon disk brakes are the best and everything should run them. Yeah, they're spectacular for a formula-1 car. But even formula-1 cars can't get them up into their operating temperature in the rain, making them terrible for anything else.

For street use the lowest level of friction that will get the job done is usually best in my experience. More forgiving, easier to drive, and as long as the parts are up to the job they'll last just fine. Using higher performance parts that aren't necessary just makes crap more difficult to drive. I mean, if I need them I need them. If I don't, and it sounds like I don't, then they're an unnecessary expense that won't improve (and could actually worsen) my driving experience. If they're better for a reason and they're not just overkill then tell me why they'll work better for this application. I'm ok with a little overbuild but too much doesn't make for a good driver. I'm going to commute in this thing, not flog it on the drag strip.
Click to expand...

Get a spring and roller kit and replace the old ones in the sprag. Take a photo of the way the springs and rollers are mounted. There is only one RIGHT way to put them in, but you sure as hell can get them in wrong. You might want to make sure the pump bushing is Perfect, if not replace it. You can see how good your pump bushing is/or is not by looking at the hub(neck) of your converter. Check all bushings. By the way, if the pump bushing needs to be replaced, get the babbit one, not the bronze one. Consider getting a complete washer kit, not expensive and might be required. There is a small thimble filter called the governor screen, again cheap, and why not change it while the transmission is apart. Sonnax makes an intermediate accumulator repair kit you might want to also think about, and both Sonnax and Superior have an upgraded reverse servo piston for you. On the rear clutch there is a diaphragm spring that is known to crack, again, an inexpensive item. At the rear of the trans there is an output shaft ball bearing. Check it out too. By all means get the ATRA book on repairing the transmission. It will be full of information on clearances etc. All your parts would be available at a local Transtar parts warehouse. Google them to get the one nearest you. Hope this all helps.
Have fun and "DO IT RIGHT ONCE"
 
Johnny Dart said:
You seem to know everything. No sense in giving you any suggestions.
Sorry I even tried. Lesson definitely learned.
Good luck with your trans.
Click to expand...

Sorry you feel that way. I definitely DON'T know everything, otherwise I wouldn't have bothered to start this thread. I'd have just rebuilt my transmission and enjoyed my car and not dealt with all of this drama. But I'm also not some novice that's incapable of evaluating the information I'm getting. Yes, I had an idea of what I was going to do before I started this thread. What's good for a 500 hp street/strip car is not the same as what's good for a 300hp daily driver. If you'd given reasons why I should follow the same build plan as guys that are making an extra couple hundred horsepower or more, I would have been all ears, just like I'm listening to transman. But just saying "red plates are better because they're more expensive" doesn't cut it, because I do know better than that.

transman said:
Get a spring and roller kit and replace the old ones in the sprag. Take a photo of the way the springs and rollers are mounted. There is only one RIGHT way to put them in, but you sure as hell can get them in wrong. You might want to make sure the pump bushing is Perfect, if not replace it. You can see how good your pump bushing is/or is not by looking at the hub(neck) of your converter. Check all bushings. By the way, if the pump bushing needs to be replaced, get the babbit one, not the bronze one. Consider getting a complete washer kit, not expensive and might be required. There is a small thimble filter called the governor screen, again cheap, and why not change it while the transmission is apart. Sonnax makes an intermediate accumulator repair kit you might want to also think about, and both Sonnax and Superior have an upgraded reverse servo piston for you. On the rear clutch there is a diaphragm spring that is known to crack, again, an inexpensive item. At the rear of the trans there is an output shaft ball bearing. Check it out too. By all means get the ATRA book on repairing the transmission. It will be full of information on clearances etc. All your parts would be available at a local Transtar parts warehouse. Google them to get the one nearest you. Hope this all helps.
Have fun and "DO IT RIGHT ONCE"
Click to expand...

Awesome. Again, thank you sir for taking the time to lay all that out. This is the kind of info that I was looking for. I'll tear my transmission down first and check the tolerances/clearances before I order my parts, so hopefully I can just order everything at once, get the right parts and reassemble in one go.

Here's a picture of the hub on the original converter. Sorry for the dirt it's been under my bench for a few years, just like the transmission. It does have a crack, which I'm told is pretty common on the earlier 904's, but the hub is smooth. Probably should just replace the pump bushing anyway. Obviously I'm replacing the convertor.

IMG_4277.JPG


This is the manual you're talking about right?
ATSG-a727_904.jpg


I've already got the 727 book by Carl Munroe, but the ATSG book looks like a good one to have too. This is the one I've already got
51POdlFm7XL.jpg
 
72bluNblu said:
Sorry you feel that way. I definitely DON'T know everything, otherwise I wouldn't have bothered to start this thread. I'd have just rebuilt my transmission and enjoyed my car and not dealt with all of this drama. But I'm also not some novice that's incapable of evaluating the information I'm getting. Yes, I had an idea of what I was going to do before I started this thread. What's good for a 500 hp street/strip car is not the same as what's good for a 300hp daily driver. If you'd given reasons why I should follow the same build plan as guys that are making an extra couple hundred horsepower or more, I would have been all ears, just like I'm listening to transman. But just saying "red plates are better because they're more expensive" doesn't cut it, because I do know better than that.



Awesome. Again, thank you sir for taking the time to lay all that out. This is the kind of info that I was looking for. I'll tear my transmission down first and check the tolerances/clearances before I order my parts, so hopefully I can just order everything at once, get the right parts and reassemble in one go.

Here's a picture of the hub on the original converter. Sorry for the dirt it's been under my bench for a few years, just like the transmission. It does have a crack, which I'm told is pretty common on the earlier 904's, but the hub is smooth. Probably should just replace the pump bushing anyway. Obviously I'm replacing the convertor.

View attachment 1715070647

This is the manual you're talking about right?
View attachment 1715070651

I've already got the 727 book by Carl Munroe, but the ATSG book looks like a good one to have too. This is the one I've already got
View attachment 1715070652
Click to expand...
The books are the right ones. Glad you got them. Look at the hub on the converter and you can see the wear where the bushing rides. The pump bushing needs replacing. Even without the crack, if it was my car, the converter would be replaced.
The red friction/koloene steel setup is very controversial. Some racers love 'em, some say they're a waste of money. Like everything else, each to their own. I know a very smart transmission builder that runs in Super Gas and he says that with Raybestos waffle plates, and with normal steel plates in his transmission he can get about 3 seasons on them. Now, my ex boss runs a low seven second car with a Steve Schmidt bb Chev , abt 12-1300HP, with a 904 behind it, and he does use the red plates/kolene steels in his transmission.
 
Well I said my apologies and I'm back in the battle here LOL and for the record my experience is taking apart the 1968- 904 and actually rebuilding a 76- 904 and you all know the results of that that's as far as my knowledge no guru here at all. But that experience I did take the 68 apart and it had less clutches and seemed a lot less well for lack of better terms as beefy as the 76 transmission did. I added that because sometimes it could be just the transmission that you rebuilding is better. when I was looking up the numbers for the Transmissions you could find out what they originally went behind a 360 or 318 or a cop car or heavy duty and stuff like that. From what I can tell from what I've seen and the results I've gotten out of the normal rebuild kit without any special parts are pretty good. I did mention a transmission shift kit and I put in a stage 3 like I said, but I would not recommend that for a street driven car as you do have to shift everything up and everything down no matter. The stage two gives you all the shift performance of the stage 3. The transgo shift kit feels Crisp without banging.
 
70aarcuda said:
I build my own 904 for bracket racing..I use stock discs and steels....A stock rebuilt kit will would just fine...get everything cleaned...check your clearance on your clutch pacs...

They are so simple the guy post above mine could do...

Transtar Super Deluxe Overhaul Kit for Chrysler TF6 (A904) 60-Up from Northern Auto Parts

I have a great video that walks you thru the rebuilding of a 727...and the 904 is very similar in design....It is free...just send me your email address and I will send you a link for the download...it is 4.7 gb so dont have dial up...
Click to expand...
I wouldn't mind this video link since the 727 is in and I'm about to rebuilt the 904, [email protected]
 
Break out your digital calipers and measure the grooves in the frictions. I did. Grooved frictions have 20% LESS surface area than smooth ones. That means that 4 smooths have the same contact area as 5 grooved. But stock smooths are weak and they're too thin for third gear heat. The stock third gear frictions are thicker and grooved because the factory material can't take the heat, shifting at 6k rpm; whereas the forward clutch with its thins; is engaging at under 1k rpm. The solution is to run smooth thin .061 Red Eagles in both drums. You can add an extra plate plus get rid of the grooves in the third gear drum. It's like running six frictions instead of four. That kit is for dummies.
 
Not trying to hijack the thread but what about building a 904 built for 500hp
Is there an all inclusive kit or will I have to scrounge for parts. I have good mechanical skills but limited tools and absolutely no place to work on one. I’m considering buying a unit ready to go although expensive with a warranty.
 
You must log in or register to reply here.
-

Back
Top