Hmmm, I have always been told not to use a gasket and rtv together or are you thinking something else?Gasket and skim coat of flange sealant. For that area
I’m about ready to Jb weld it together…I tried everything in my power to get my 208 to not leak there and have yet to be successful.

I went as far as using a wire wheel on a grinder to lacquer thinner to clean it…Paper gasket and rtv. Mine didn’t leak there with that combo.
I use a very thin amount on both sides of the gasket with both mating surfaces clean of garbage.
That thought crossed my mind but my luck it would still leak and then I’d have to sawzall it off haha.I’m about ready to Jb weld it together…
What trans?
I just use a gasket thereI think I’m not explaining it right. That o ring is in and not leaking it’s the tcase side as in between the adapter and tcase.
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That might be a good idea! I’ll have to try it next time. This weekend I’ll just bring a few quarts of atf… it’s only 350 miles…….not rtv, flange sealant https://www.amazon.com/gp/product/B002C3CGMS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 I use this stuff in a lot of places, out side of metal seals, sometime the splines on yokes.
the surfaces of the adapter and the t case are essentially flanges.

Have a temp gauge and will go half way and check.be sure to keep an eye on the level, a slow leak is the trans killer, not the catastrophic
I wiped down the breather tube and moved the truck 20 feet, over night it’s leaking out and the fill plug is leaking to. I think Both are leaking, on poison spider hill you could watch it pump out.I don't believe that the input seal on the T case would make it leak from the adapter housing. It would overfill the T-case, yes.
What's your thoughts on this?