I have a 66 289 auto trans. About 9 months ago, after driving around, I parked her, and the next morning about a quart of tranny fluid was on the ground. I filled it back up and had no trouble for months.Two weeks ago I drove to my storage space for her internment for the winter. All was fine until today when I noticed another big tranny leak. Any ideas? P.S. the storage space it heated. Thanks

 

Sounds to me like she's marking her territory.

 

First time you noticed was the car on a hill pointing down?
Second time how long did it sit?

I would think you prob have a leaky dipstick tube. During quick stops (like overnight) if you are on a hill it can be prone to leak out some where on flats spots it might not. During longer periods of sitting the fluid in the TC will tend to seep out into the trans raising the level more and if you have a leaky spot in the dipstick it will come out. Notate where the puddle is before you move the car next time. If it is centered under where the bell bolts to the block and favoring the passenger side it is simply a dipstick leak.

 

It might be the torque converter draining back into the tranny. mine was doing the same after sitting for any period of time. look closely under the car and see if it's leaking out the vent tube on the driver side. if so, you can bendanother tube, 5/16, andmake it turn up about 10-20 degrees for about 3-4 in. and then down. this will causethe fluid to flow back into the tranny and not out the tube, yet still give the tranny ventilation when you're driving. once you unbolt the retaining bolt, it's just a slip joint and you can easily remove the tube by hand, anduse the orignalas a template for the new tube. bend the new tube up, after the point where it bolts to the retainer. you'll know what I mean when you see the original tube. Another option is to simply add some rubber hose to the vent tube and turn it up, but that may cause a collection of fluid in the tube resolt in difficulting with venting.

 

When I rebuilt my suspension, my car sat on stands in the garage for almost a month. 2 days before I finished it up, I was under the car working, looked back, and out of nowhere the tranny was dumping about5 drops a second out of the pan. Never did figure out why. Once I got the car back on the ground and started, problem stopped.