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727 torque converter drain back

Dan

Dan

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Had my 727 rebuilt and still have a converter drain back problem. After sitting for two days when started and put in gear it takes about 30 to 45 seconds before the car will move when in gear. I know you 727 guru's out there can tell me what part should have been replaced when the trans. was rebuilt. I have had this car for over 30yrs and it has had this problem for longer than I can remember.
 
drain back is an annoying issue. i've found that the best cure, for me anyway, was simply to start the car in nuetral if its been sitting a few days. a nuetral start gets the pump working immediately at filling the converter. the tranny in my 65 coronet was so bad about drain back that the converter would loose fluid in a couple of hours if the car sit at an incline. the builder told me that his "shift kit" mods contributed to the drain back. i eventually "did" my own valve body and cured most of the problem.
 
Mopar muscle magazine had an article on that not to long ago, ckeck there web sight. Good Luck
 
Convertor drain back is a common occurance on 727's. You can put a check valve in the trans cooler line to stop it.
 
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Factory reps were telling us at the dealer what "lewtot184"said to start them in neural and it seemed to work.
 
Seems like I remember reading a TSB about it and how the factory remedied the problem but ellifI remember. CRS disease I guess. Anyways, even my 97 Dodge diesel does it but my 2000 Durango nor my 95 Dakota does it.
 
Cranky said:
Seems like I remember reading a TSB about it and how the factory remedied the problem but ellifI remember. CRS disease I guess. Anyways, even my 97 Dodge diesel does it but my 2000 Durango nor my 95 Dakota does it.
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i had a '96 ram 1500 that did it.
 
My '70 GTX has it after a couple of days but starting in neutral helps. My 2000 Ram 2500 (250,000 km.) has it after a week or so of sitting.
 
These guys are right as most older 727's have some drainback. Mine does after sitting a few days. But if you start it in Neutral like was said it usually cures it as then it only takes a few seconds. Thats because the 727 does not circulate the fluid in park but all other gears do so in Neutral the fluid will fill the converter as soon as you start it. Ron
 
Old thread but has anyone installed a check valve in the return line? Where can I get one of these? Mopar part #?
 
toolmanmike said:
Old thread but has anyone installed a check valve in the return line? Where can I get one of these? Mopar part #?
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wish i knew the answer. my '69 coronet will drain back in hours. i know this is an old thread but if there's any new info i'd like to hear it.
 
lewtot184 said:
wish i knew the answer. my '69 coronet will drain back in hours. i know this is an old thread but if there's any new info i'd like to hear it.
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My 70 Swinger does it. I had 2 96 Dakotas. One did it, one didn't. All are 904 based transmissions.
 
Dan said:
Had my 727 rebuilt and still have a converter drain back problem. After sitting for two days when started and put in gear it takes about 30 to 45 seconds before the car will move when in gear. I know you 727 guru's out there can tell me what part should have been replaced when the trans. was rebuilt. I have had this car for over 30yrs and it has had this problem for longer than I can remember.
Click to expand...
TransGo shift kit has a new manual valve and a couple modifications that will cure the problem. Or as mentioned just slip it into neutral for a few seconds, fill the converter and then go into gear.
 
toolmanmike said:
Old thread but has anyone installed a check valve in the return line? Where can I get one of these? Mopar part #?
Click to expand...
The converter drains back into the pan internally is what I understand.....
 
Cranky said:
The converter drains back into the pan internally is what I understand.....
Click to expand...
Yep. I know that now. Back in 2017 when I posted I didn't know. All the Mopars I have owned never had the issue until my first Dakota then my Swinger. Until then I didn't know it was an issue.
 
toolmanmike said:
Yep. I know that now. Back in 2017 when I posted I didn't know. All the Mopars I have owned never had the issue until my first Dakota then my Swinger. Until then I didn't know it was an issue.
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I bought a 72 Challenger in 74 and it did it.....had 40k miles on it lol
 
Cranky said:
I bought a 72 Challenger in 74 and it did it.....had 40k miles on it lol
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HA! I had 2 73's in 78.

253.png
 
toolmanmike said:
Yep. I know that now. Back in 2017 when I posted I didn't know. All the Mopars I have owned never had the issue until my first Dakota then my Swinger. Until then I didn't know it was an issue.
Click to expand...
And didn't notice it was from 17 lol
 
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