727 Big Block Info

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KOZ45

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Need some info on the 727 trans in my Duster........

440 swap, so I am assuming it has to be a 727 big block auto

Are all big block 727 trans the same? Are the cases stamped or marked at all to help ID it?

The trans was operational when it last ran, like 5 years ago. Will the trans still be good? The PO said the fluid in these transmissions gums up after sitting so he wasn't too certain how the trans will work.

I hope to get the car running over the winter, so I am just trying to plan for the spring.......to see if I need to pull the trans also? If its broke...... its broke, so I just plan on getting up up and running and see how the trans responds.

What's the general consensus on the 727 when they sit with fluid
 
I'm wondering why the po would say something so ridiculous. Maybe he knew the trans was bad. Start it and check the level in neutral. Don't run the motor for more than a minute with the fluid level low.
 
I really think he was being honest and didn't want to guarantee the trans would work

He had a shop full of restored Mopars (that he did) and said the fluid seems to really gum up the internals after it sits for a few years
 
The fluid doesn't do that. There are a lot of car experts out there who are stopped cold by automatics. They assume things they've heard over the years are true, and pass that incorrect info along. I always recommend starting a project with a 71-78 transmission to take advantage of the part throttle kickdown and wider direct drum support.
 
Look at the pan rail on the driver's side for the part number and date code.

You can also check to see if it has a VIN pad on the passenger side of the bell.

Those numbers will tell us more. (photos help)
 
I agree, look for one with part throttle kickdown. Sorry, cant tell you the year they started that off the top of my head.
Another big plus is 4 pinion planetarys. The HP cars usually had them and some trucks.
 
Driver's side of the transmission, near the lip of the pan:

PK2892092L 2797 0616
 
There is a VIN looking number cast into the transmission case, on the passenger side. Its pretty hard to read though

Here are some pics I was able to take..............again, thanks for any and all info!!


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I will probably gamble and just check the fluid and run it...........fingers crossed

What trans fluid is suggested?
 
Thanks for all the info!!!

So many people, locally, told me the trans is likely shot since it sat this long with fluid in it........
 
Well you got two choices 1 is check the fluid levels or change the fluid and filter in go with it and see how it works.
And your second choice is rebuild it.
Personally I'd pull the pan change the filter and put fresh fluid in it and go with it if it doesn't work it doesn't work but if it does work you just saved yourself a rebuild.
 
A lot of the transmissions that come in for rebuild have just had their fluid changed; converter and all...I drain it all out for them....10 quarts X $4 per quart= $40...and into one of my cars it goes. I haven't bought new fluid in probably 6-7 years. Way back, Rossi Trans was selling 10wt motor oil as "racing transmission fluid"...you can dump any kinda crap into a Torqueflite. I knew a guy who blew a line out in the desert late at night. Needed two gallons. Put a case of Aquafina in it and drove it back to town. Changed it the next day...no problems...jis sane...
 
So it sounds like a pan drop and new filter might be a good idea

Any tips or tricks to get as much of the old fluid out, as possible, with the 727 installed?

I'll add that to my "to do" Duster list

RTV or actual pan gasket?
 
If you want to get the most possible fluid out you drop the pan, remove the filter and move the selector through the gears. Let it sit 5-10 minutes in each gear to let it run out. You can get even more out by lossening the valve body bolts but its really not necessary. Drain the torque converter if it has a drain plug (not all of them do).
 
...I see a leaky pan in somebody's future...Sealing a pan gasket is an art form. First you have to be a body man to straighten the pan; actually, knocking up the area around the holes to preload the area between them; at least 1/16"... Check it with a straightedge. Then choosing a stiff fiber gasket; Duprene brand... NO SEALER of any kind. No oil allowed on the contact surfaces; clean and dry. Bolts TIGHT. Just don't strip the threads out of the aluminum case.
 
Thanks I appreciate it

How much Dexron 3 should I have ready?
 
While you've got the pan off and the filter you might as well adjust that rear band also.
 
Here you are already deciding to change the fluid and filter without even seeing what's in the pan...waste not; want not..There's nothing magical about changing fluid and filter. It's not a fixall; more of a routine maintenance procedure...Unless you think maybe some water got in there..otherwise it's just fixing something that isn't broke...How's that saying go?
 
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