Car only leaking transmission fluid after driving?

Okay so I know this sounds weird, but my car only leaks transmission fluid after driving. I originally thought it was my pan gasket because I just did a fluid and filter change but it wasn’t. Also just replaced both CV axles and axle seals. Anyways, turned out I was incorrect because it’s still leaking. I let it idle in different gears for around 15 minutes in my driveway to warm up the transmission fluid, no leaks. I drive it, park it in the driveway and it’s leaking out fluid. It’s a slow leak but it ends up leaving a big puddle. The transmission is a touch overfilled according to the dipstick but I might’ve been running a little hot due to driving on a hot day in the city. I feel like MAYBE it’s because it’s overfilled or it might be one of my cv axle seals and maybe it drips down around the pan gasket which made me think it was the pan gasket, but after buying a $50 reusable gasket and loading it up with gasketmaker, it’s still leaking the same. Everything was fine before I took a 12 hour trip. Below are some pictures of the leak:

These are some more pictures uploaded in a seperate comment because All the files at once we too large in the comment above:

Are you sure that is transmission fluid and not motor oil?

POSITIVE. It’s literally red :man_facepalming:t2:.

Replace the axle shaft seals.

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I just replaced both of them tho! They were a pain in the ass! I was thinking that maybe my cv axle Isnt in all the way but I would think it would’ve fallen out on my 12 hour trip. Do you think it looks like it’s all the way in?

Shaft looks all the way in and the seal looks like it was damaged during installation. The metal shell shown in the picture is clearly bent. It should not be. It needs to be replaced again.

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I wouldn’t have thought that little bend would cause any issues because the rubber seal on the inside looked totally fine but you might be right… probably in denial about spending another hour trying to get that thing in xD. Might just pay somebody to fix it at this point, thanks.

It looks like overfill to me. Have you checked your COOLANT level? Maybe coolant is entering the trans by way of the radiator. I believe coolant is heavier than Dexron fluid so it would force the trans. fluid out the overflow vent.
Is the fluid milky looking on the dipstick after driving? If so, it’s contaminated.

No it’s definitley not coolant. I changed the fluid once when I did the filter and fluid and then once again when I thought it was my transmission pan leaking. The fluid was fine. No discoloration whatsoever. The transmission is a little bit overfilled though but that’s because I accidentally put to much in. I did the amount it told me to do in the manual but it ended up overfilling!

In the very first photo, I can trace the line of fluid from the bottom of the seal, then down and underneath the housing…it was the very first thing I noticed. In my opinion, it’s the seal.

With that bent metal shell, think of it like this: the outer edge of the shell is connected to the inner edge of the seal, right? And the metal itself is fixed in size/volume, right? So my having it bow outwards like that, you’re actually causing it to pull on the inner edge of the seal, which also pulls the outer edge of the seal away from the axle housing, just enough for some fluid to get by. At least that is my theory.

I agree with you. I definitely think the seal is leaking fluid I just didn’t know if its doing that because the transmission is a little overfilled or maybe it’s a combination of the pan and gasket. In the top left of the picture below, you can see the axle housing where the transmission fluid is coming from. What I’m confused on is why the transmission fluid looks like it’s coming from the transmission pan gasket if it’s only coming from the axle seal. I let my car warm up and idle and there was no leaks. Took it for a ten minute drive and when I get home and park it, it’s leaking again. I understand transmission fluid expands a lot so I was just thinking maybe since it’s overfilled, it’s expanding and leaking from the seal. I think if that was the case though it would be leaking from both axle seals; only my passenger side is leaking.

Leaks usually don’t go up but driving can have an impact. Generally, the highest point you see fluid is about the point it is leaking from.

The seals/gaskets shouldn’t leak no matter how high the fluid is. Their purpose is to seal.

The fact it only leaks when you drive also points to the shaft seals. And one of them is clearly damaged.

You can keep looking but I think the prime suspect has been found…

It could easily leak from the seal and just flow around the edge of the transmission pan due to surface tension. It could also be that fluid is being thrown from the leaky axle to other parts of the casing while driving.

I think you need to let go of the leaking pan gasket idea…you’ve got circumstantial evidence for it at best.

Okay thanks for all the opinions! I will replace it this weekend and see if it fixes the problem.

You may want to consider taking it to a professional; how exactly did you install the seal last time, that it got so damaged?

I actually have a seal installation tool but it was hard to get a hammer in there so I tried to use an extension that goes on a ratchet and that wasn’t such a good idea as you can see. The other side wasn’t nearly as bad because the way the steering had the knuckles turned