Stubborn A/T oil leak

[papa_g]

So I have been battling a leak from my transmission as the car was sitting in storage. A decent size wet spot developed on the transmission. When I got under the car, I saw the leak was primarily from the rear driver side corner of the oil pain, possible from the fill plug, and a small amount from the selector shaft seal.

For context:
- Currently at 119K miles
- GM A5S390R
- New transmission filter, gasket and fluid at ~88k miles (I think there was already some leaking as the oil pain was pretty caked in oily residue.
- Developed leaking again around 114k miles, so changed gasket again at 116k miles
- There was still leak, narrowed it down to the drain plug and selector shaft seal --> at 117k changed drain plug (fixed) and placed selector shaft seal o-ring and washer (theres a DIY somewhere).


Now I am still getting an annoying leak despite 2 gasket changes. The selector shaft seal leak is something I may have to keep troubleshooting if it continues, but what do I do about the gasket? RTV is not required here per the Bentley manual, but should just do it anyway? Should I torque it beyond the spec?

Appreciate any help guys.

[papa_g]

Here you can see where the ATF leaks out. It seemed to me like there was some in the fill plug as well, but it is relatively new and fully torqued.

[Will]

I would not over tighten the oil pan bolts, they felt like they would strip easily. If I remember correctly, their torque spec is something very small, like 7lb/ft. I recall they didn't feel "tight." But spec is spec and no leaks.


Are those bolts original BMW? I had some that looked like yours when I ordered a FCP euro trans fluid and filter kit. I did not use them since some did not thread in smoothly. I ended up reusing the OE BMW ones.

Maybe drop the pan and re-do the gasket, and have a small torque wrench?

I'm not sure about the shift selector seal. I have no experience with that.

[papa_g]

No these are not genuine bmw. They are also from a fcp euro set, but they came with threadlock and went in smoothly.
You’re right, the torque spec is very small, and I used a small torque wrench.

[racer2086]

Is it possible the flange of the pan is bent? Using a BMW gasket?

[papa_g]

Is it possible the flange of the pan is bent? Using a BMW gasket?

Possibly bent, but I don’t know how it would’ve happened.
It’s oem or OE from fcp euro

[racer2086]

If you loosen all the front bolts from the pan first and let it hang from one or two, I could see that stamped steel flange bending. Just trying to come up with ideas.

[papa_g]

Yeah. Im skeptical that happened though because when removing the pan, it’s usually caked on to the gasket and tranny, and requires some wiggling to remove