Need help identifying a 904 Transmission and Torque Converter

[Dixie]

Hey Guys,

Seems the 904 in my son's Demon bit the dust. A guy in my local Mopar club has a 904 rebuilt with about 5K miles on it with choice of TC's for $300. He gave me some numbers off of the side of the tranny, but I can't find anything to decode them. I'd like to know what gear ratio is in the tranny and what it came out of. My son's car is a slightly warmed over 360 with 2.94 gears. I would appreciate any help you give to ID the tranny. Here are the numbers:

402 8464 5522 0834 - on rail

7B175505 - on body (probably the VIN)

0861 - bellhousing

Also, he has 2 TC's to choose from, but doesn't know the stall of either. Is there anyway to ID or test that?

Thanks !!
Randy

 

[Oklacarcollecto]

Hey Guys,

Seems the 904 in my son's Demon bit the dust. A guy in my local Mopar club has a 904 rebuilt with about 5K miles on it with choice of TC's for $300. He gave me some numbers off of the side of the tranny, but I can't find anything to decode them. I'd like to know what gear ratio is in the tranny and what it came out of. My son's car is a slightly warmed over 360 with 2.94 gears. I would appreciate any help you give to ID the tranny. Here are the numbers:

402 8464 5522 0834 - on rail

7B175505 - on body (probably the VIN)

0861 - bellhousing

Also, he has 2 TC's to choose from, but doesn't know the stall of either. Is there anyway to ID or test that?

Thanks !!
Randy

I am not aware of any different gear ratios on an automatic tranny unless it is for an overdrive. The gear ratio is in the rear end. If I am wrong someone will chime in.

 

[Dixie]

I believe there were different internal gear ratios available.

 

[Oklacarcollecto]

4028464 is listed as a standard A-904-1 used behind a 318 in both 1976 and 1977.

The only ratio differences that I know of is for an overdrive tranny but Lord knows I am not a tranny guru.

 

[Dixie]

Ok, thanks!!

 

[fishy68]

It's possible it's a low gear set 904. They started using them in the mid to late 70's when 318's were so choked down. I know how to spot a low gearset 904 when it's apart but no idea how to identify them by the numbers. The only decoder I know of just tells the year and engine it came behind. Same info as OK gave. JFYI here are pictures of the front planetary gearsets on std and low gearset 904's, also known as a wide ratio trans. You'll notice the sun gear has more teeth on the front end than the back on a wide ratio trans. On a std ratio trans they are equal teeth

No help on I.d.'ing the converters but I'll say I don't like dealing with used torque converters unless it's verified good by a rebuilder. So many I've seen had wear on the neck or crap in them cause somebody installed it in a car that previously had a burned up trans. and they didn't flush the cooler and lines. If I were you I'd buy a new converter keeping in mind that 360's are externally balanced so they take a weighted converter specifically for them. Use a 318 converter on them and expect it to shake violently.

Also keep in mind you need to flush your cooler and lines in your son's car to get the crap out of them or the new trans. won't last long

 

[Robj]

Did the non-OD cases change at all in length or otherwise other than the later OD trannies?

I have a '74 904 out of my son's 318 B-body that I'd like to rebuild and use to freshen up the tranny in my '70 318 Dart. The mounts are different between the two cars but will the case accommodate either mount? I want to avoid much down time and also the need to modify the driveshaft. I always believed them to be the same but figure I should check.

 

[fishy68]

Did the non-OD cases change at all in length or otherwise other than the later OD trannies?

I have a '74 904 out of my son's 318 B-body that I'd like to rebuild and use to freshen up the tranny in my '70 318 Dart. The mounts are different between the two cars but will the case accommodate either mount? I want to avoid much down time and also the need to modify the driveshaft. I always believed them to be the same but figure I should check.

I believe all 904's are the exact same length, the only exception might be the early cable shift trans. There is only one thing you might run into trouble with if your Dart is a factory floor shift. Not all tail housings had the lower shift bracket mounting ears. If your Dart is a column shift or has an aftermarket shifter installed you don't need to worry about them.