Transmission oil leak

[bigallant]

This is a 2001 Mercury Sable V6 24500 miles. Never had a problem with it.

What would cause transmission oil to leak several days AFTER being parked (I do not use the car that much). The car, after a 180 mile trip, ~70 m/h at the most, began leaking trans oil after being parked for a week without leaking (the first week, no leak at all). Then it stopped leaking, then started leaking again after a couple of days. Is it possible that there is a pressure build up by just sitting there? I presume that it leaks because some type of pressure is building in the transmission. By the way, I’m 95% sure it is coming from the spout where you add the transmission oil because there is a little puddle of oil on the top of the transmission right under the head of the spout. The leak is not coming from the pan.

Two weeks later: It has not leaked for some time now (~two weeks), but I’m thinking that it is because it is low.

I just took the car for a spin (~2 miles) and it appears the transmission is now slipping. It slips after it is warmed up. It seems like at 25K miles I should not have transmission problems.

So, since the transmission was slipping, I checked the level of the trans oil. When I pulled the dip-stick, with the car heated up and the engine running; it was dry. So, I added 1 1/2 quart of oil, and the slipping stopped. I drove around for ~30 miles; then parked the car. The following day, no leak, I was so happy. Then I took the car for yet another spin later that evening ~4 miles, parked it, went into a store; when I came out, there it was the familiar puddle of transmission oil again (my 1 1/2 quart of oil was all over the parking lot). Is there something that supposed to release pressure in the transmission and it is not doing its job, so it causes it to leak when it is parked. It does not leak when it is running. I read somewhere that if the breather port is clogged, it could cause it to leak through the spout. But, I do not know if this car is equipped with a breather port/hole. I must repeat, the transmission is NOT over full/filled. Even after adding the 1 1/2 quart of oil, the oil was barely in the hash mark of the dip stick.

Let me know if you need more info.
Please help
Bill

[DanD]

I can’t think of anything that would build pressure after the vehicle has been shut off to cause this leek; but way2old is our resident Ford man that may know of some service bulletin that addresses this issue?
What I have seen is the transmission cooler lines rust and begin to leak; causing the fluid to puddle in the engine cradle and then slowly drip off making it look like it only leaks after the vehicle is shut off.
Get under the car and have a look; to see if you can see where the leak is originating from???
Dan.

[way2old]

Good advice Dan. Other thing is the vent being plugged or the dipstick tube seal is leaking. It will only leak when engine is off, because that is when all the fluid is dropping back into the pan.

[idol]

If the fluid is leaking after sitting it is possible that the torque converter is bleeding back into the transmission causing it to overfill and leak. When you start the car and drive it, the pump begins to fill the converter first, hence the tranny fluid level will be low. This will result in a slipping problem.
There is no home test for a bad torque converter unfortunately. I would recommend taking the car to a tranny shop and have them do a leak down test. I feel confident that the torque converter is the problem.
.......please let us know what you find....IDOL