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My transmission around the cap, is there any way to make it stop leaking.
I thought about trying to replace the inner seal on the cap, but not sure I can, without messing things up.
What I am seeking is a solution to stop the leak around the dipstick cap. Is there one?

Can you post a photo of the cap? Caps are available from vendors but you might also just be able to rivet it back together if you fix it yourself.

Did you check the transmission fluid level and make sure it's not overfilled? I would be surprised if so much splashed up the tube that it would cause a significant leak.

I agree with PGH Ultramatic, easy enough to get a replacement cap/dipstick and also seems unlikely enough would splash up the tube for it to leak, even if the seal was bad.

But you do want a good seal to keep dirt and water out of your transmission!

I agree with the other posters that you should not see a leak at the cap. The only reason I can think of for this might be pressure build-up in the tranny because the vent is plugged. Check the vent on top of the transmission and make sure it is not plugged. You access the vent from inside the car, under the carpet on the transmission "hump", there is a small plate that can be removed. The whole vent unit can be removed with a 1-1/4" socket.

There should be a cap on the vent. Be careful to not lose or damage it as they are scarce.

Thanks for your responses, I have the dipstick cap in place, but I think the seal is not tight enough. I will check for a vent cap. The fluid is at the proper level.

My dipstick gets quite snug before it hits the stop. Is this how yours is? Does it look like this?





The vented fill plug on the top of the transmission looks like this.

You and I have exactly different problems. The fill cap is the only place my Ultramatic doesn't leak from.
When you tighten it down does it kinda feel like a radiator cap ? Like there is something the cap is pushing against to make it tight ? If not, like it kinda rattles loose on top of the tube, you might need a new cap.
If its pushing fluid out of a tight cap, i would check that breather.
I am no pro with Ultramatics, but pushing fluid up and out a fill tube sounds like pressure building with no where to go.

Yes my dipstick cap looks the same as your picture, the vent cap you shoe, I will locate mine and make sure it is in good condition. Thank you.
Any ideas who might offer a new cap for sale?

Yes my dipstick cap looks the same as your picture, the vent cap you show, I will locate mine and make sure it is in good condition. Thank you.