Your 'Guide' to the 727/904 transmission

Ghostrider 67

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OK, not sure which springs you are talking about since there are many springs in a 727. The front servo springs, front clutch return springs, various valve body springs. All make a big difference in how the 727 performs.
True, I may not have been clear. I'm talking about the valvebody springs. I have laid out the springs and noted colored ones ( racist!) and the valves as well and numbered, lettered all for Tom Hand to look at and see if he can ID them all with location and match up to each valve etc. waiting to hear back.
THIS guy.....

If he doesn't know then I'm screwed...lol.

20210304_105040.jpg


Here's what I sent him..
InkedInked20210304_075552_LI.jpg
 

66Satellite47

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I don't know about that book. I'm pretty sure a FSM for the year of 727 you have will show you what you need to know. Otherwise just buy an aftermarket valve body to match your intended application.
 

440 Charger

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I agree. I have the trans rebuilt with no issues. Just the valve body left to do. Tom Hand is assisting me with id on the springs.
Ghost, you will be amazed at how often the factory service manual can help you. You just need to avoid being hung up on all the "special Mopar" tool numbers & figure out available tools can do the job. Once you digest the details, a 727 is very simple. Using the correct combination of internal parts for your application is important.
Have to make it silky tough.
 

Ghostrider 67

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I don't know about that book. I'm pretty sure a FSM for the year of 727 you have will show you what you need to know. Otherwise just buy an aftermarket valve body to match your intended application.
Tom Hand is the Transmission Guru. Period.
 

MoparLeo

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Tom can't help you with the rest of your car... Get a Factory Service Manual. I left you the link for free ones...
 

Ghostrider 67

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No room for learning there.
I always take my knowledge from as varied a number of sources as possible. Please don't anyone get their backs up because I didn't latch on with both hands to your suggestions. I HAVE an FSM for my vehicle. I find Tom's book to be simply easier to navigate and has better illustrations and in depth coverage of many aspects of the 727. Thanks to all who have chimed in with timely and valuable suggestions. I appreciate everyone's input. I have, as I mentioned, already built the 727 that's going in my car. This unit is an extra one that will be sold. I didn't drop the parts on MY trans, but did on this one. I just didn't want to have to open up MY trans to investigate where each spring went. Okay? Thanks.
 

Moms68

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To fill or not to fill- 904 torque converter??

I got my rebuilt 904 back from the shop. Should I fill the torque converter before installing the tranny?
 

MoparDanMan

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Often I or anyone for that matter asks to find out what type of transmission they have in their old mopar. There are hundreds, if not a thousand, of threads on this website identifying, discussing or assisting with this process, troubleshooting or repair.

Because of this large number of threads and the fact that using the search option is unbeknownst to some members, I have put this together.

FIRST AND FOREMOST, HERE IS FRONTAL PICTURES OF THE /6, SB, AND BB TRANSMISSIONS:

View attachment 455769

HOW TO IDENTIFY YOUR TRANSMISSION:

1. Do I have a 727 or a 904?

The picture of the 727 transmission is first, the second is a 904 transmission –


View attachment 455770
View attachment 455771

Gasket pictures to see what you may have from a bottom view

View attachment 455772

2. Here are pictures of 4x4 transmission 727 on the left and 999 on the right

View attachment 455773

3. Where do I look for the identification number’s on my transmission?

You will see a set of numbers starting with “PK” on the driver’s side of the transmission above the tranny pan but below the shifter levers, see below:

View attachment 455774

View attachment 455775

The passenger side carries with it (if its 69 model year only) the complete VIN of the vehicle, 1970 and above have the year, place of manufacturer, and serial number of the vehicle it was made for, see below:

View attachment 455776

4. What are the differences between a A518/46RH, a 904/999/A500 and a 727?


View attachment 455777

View attachment 455778

5. What do I have to do to put a OD transmission in my older vehicle?

Here is a start. There are many sites that cover this swap, but this one is pretty good to get you going.

http://www.transmissioncenter.net/SwapInformation.htm

6. Why is a 727 called a 727 and a 904 called a 904?

The 904 was originally called the Torqueflite 6 and the 727 was the Torqueflite 8. These designations were changed in '64 when the 904 was adapted for use in the new 273 V8 and was no longer a 6 cylinder only unit.

7. What is the difference between a truck and a car tailhousing?

TRUCK HOUSING:

View attachment 455779

CAR HOUSING:

View attachment 455780

8. What is the difference, externally, between a 65 and below 727 and a 66 and up?

65 and below will have the parking brake mechanism located on the outside of the tailshaft housing (see right silver transmission), and the transmission mount is located in a difference place, and has wider bolt/stud mounting holes.

View attachment 455781

Also, 65 and below were a pushbutton design:

View attachment 455782

9. What are the differences between the shift levers, are there any?

Generally, a 727 shifter lever is straight and a 904 is offset (though some applications have different length of levers to compensate for vehicle model/engine combinations).
727 on top, 904 on bottom:

View attachment 455783

10. This will give you an idea to the different styles of throttle pressure (aka kickdown) levers:

View attachment 455784

11. Good reference on what each port does in the transmission case:

View attachment 455785

12. BREAK DOWN OF A 727:

View attachment 455786
View attachment 455787
View attachment 455788

13. DIMENSIONS BETWEEN 727 AND 904:

View attachment 455789

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Remember, only smallblocks have 904 derivative transmissions, though some came with 727’s (i.e. certain truck and HP car models). Big Blocks only came with 727’s.
And here is a kicker to boot.. International Scout’s and other IH trucks used 727’s also.. so did AMC’s here is a pic of a AMC 727:

View attachment 455790

Great resource book:

View attachment 455791

http://search.barnesandnoble.com/Torqueflite-A-727-Transmission-Handbook/Carl-Munroe/e/9781557883995

WELL THAT ABOUT DOES IT.. HOPE YOU ALL GET A LITTLE INSIGHT FROM THIS.. I MAY ADD TO THIS AS I GO ALONG.
Thanks' that's great, brings back so many memories of rebuilding these.
 

SMS68

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I read through all of the threads so I apologize if I missed the answer, but will a late model (1985) small block 727 work with a 1971 340 in a 1971 Road Runner with out modification other than the torque converter or other internals? Will bell housing, shift linkage, and tranny mount match up?
 

Ghostrider 67

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I read through all of the threads so I apologize if I missed the answer, but will a late model (1985) small block 727 work with a 1971 340 in a 1971 Road Runner with out modification other than the torque converter or other internals? Will bell housing, shift linkage, and tranny mount match up?
get the stamped numbers on the transmission pan rail. We will look it up.
 

Ghostrider 67

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The cases were the same clear up into the late 1980's. Different things were added inside but the outside is the same. Anyone correct me if I'm wrong here. After 1978 it'll be a lock up style too...
 
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SMS68

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get the stamped numbers on the transmission pan rail. We will look it up.

Thanks, I don’t have one yet but keeping an open for one as they pop up for sale in my area. Working on other priorities first but would grab one if a good deal popped up....if I could mate it to my 340 when I get to that point.

A guy near me is selling a ‘85 318 paired with a 727 for $400. Figured maybe I could rebuild the tranny and resell the 318.
 
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66Satellite47

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yes, the case will work fine. There are many combinations of internal components for different years and different applications.
 

Ghostrider 67

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Chrysler thought, " Don't mess with a winning recipe for transmission design." They were right.
 
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