Cold Natured 727...

[kallio67]

My 67 Coronet 727 trans does not like to go into gear when it is cold...reverse or drive. When it does, it pops out before I get rolling. I cant begin to explain my frustration. Once it warms up, it goes into and stays in gear like it should and shifts like it should. Any idea what is going on? Is this an indication that a rebuild is coming.

Thanks in advance.

 

[Hemi Rebel]

Check the fluid level once its warm. In neutral. See where its at.

 

[70rr-brian]

When you say it "pops" out of gear.... I assume it acts like it is in neutral? Or does it physically go back to neutral? If you start your car in neutral and let the torque converter fill up for 15-30 seconds before putting it into gear I would be willing to bet it doesn't behave the same way. Sounds like the converter is just draining back and giving the illusion you are in neutral...But I could be wrong.

 

[kallio67]

Yes, it acts like it is in neutral...from what I can tell it does not physically go back. It will stay in gear for a second, then nothing. When I move the gear shifter from R-n-3-2-1 it does nothing. I dont hear a click or feel the trans grab. I'll give your recommendation a try this afternoon to see how she reacts.

 

[Cranky]

How many miles on it since it's had the fluid and filter changed and the bands adjusted?

 

[kallio67]

Cranky: I just recenly bought the car, so I dont know. I wont be able to get it to a mechanic until this weekend, so I'm trying to get as much information as I can to see if there is something I can do rather than have a mechanic tell me I need a rebuild.

If I change the filter and fluid, and the fluid hasnt been changed in a long time, what are the chances of that causing harm to the transmission? I've read a few posts where people have had issues in changing fluid in high mileage transmission.

 

[copper67440]

Check the fluid level first. I had a Gran Fury that would slip being just a pint low.

 

[Beekeeper]

kinda sounds like a leaky check valve too when it sits a while the fluid pressure drops to zero then when started it takes a little bit for the pressure to build back up then it will move

 

[68GTX440]

After trying the recommendations above and it stills does the same, it sounds like the seals are hard. After a little warm up they will soften up and all will work good. If you don't or can't do a rebuild right away you can try a can of Trans-X. This will help soften the seals. It may work for a long time and may not. Bottom line if all else fails you are looking at a tranny rebuild.

 

[dvw]

A couple things. First check fluid warm in neutral, not park. Second, a 904 or 727 doesn't pump much fluid in park. Let it run in neutral 30-45 seconds first. Did that fix it? That's pretty normal. Third still does it? The filter may be partially plugged. After that I would agree its got some seal ring wear. Also there is no check valve that keeps the fluid in the converter.
Doug

 

[HEMI-ITIS]

There is a valve in the valve body that sends pressurized fluid to the converter.I'm having the same problem. The valve body would have to be opened up to check or repair.

 

[monaco66coupe]

I was told by an old transmission man early on (1960's) that 727's don't pump fluid in Park, and he suggested warming the transmission up in the morning in neutral for a few minutes, Then put it in gear. I'm not disputing there could be other issues in this case, but you might try it. I even do it on my 97' 360 ram, and overdrive is off until the engine temps come up.