Leak between transmission and tcase

Anyone else have a problematic leak between their 6 speed trans and tcase, replaced the o ring that sits on the nose of tcase made it 100km and was leaking, drilled a small hole to fit a bore scope to make sure it's the same leak and sure enough it was, replaced it again this time filling the space behind the o ring with gear oil rtv, on a road trip and it's puking again, see pics for reference

 

You replaced the Oring and the seal?

 

Just the o ring, the seal on the tcase gets shoved into the trans so it wouldn't make an external leak

 

@gearcruncher will probably know...may take him a minute to answer

 

One thing I thought of is the vent plugged or the original owner mixed the vent hose with a vacuum hose and the trans is getting pressurized (should mention it's supercharged, 10 psi at redline)

 

Your second picture doesnt look proper where the seal is suppose to fit into the casing .
Looks like you had end play issues and the casing was eaten away where the seal bottoms out .
I am sure there are other pictures hanging around at Tacoma World . Certainly shouldnt look that eaten up .

Are you loosing transmission fluid or transfer case fluid ?
Looks to be transmission fluid

 

Seem to be having a hard time finding a picture to compare, if you know of one could you post a link to it please, I'll let it cool down and pull the fill plugs see what one is low, I literally just did a driveline service so everything should be full but I agree it does appear to be coming from the trans

 

BillDaCat8 is probably going to be your best bet for a picture of the rear of the transmission .
He did a swap to a 3rd gen trans . Hope he has some pictures of the rear of the transmission . Something about your picture does not look correct
https://www.tacomaworld.com/threads/6-speed-shenanigans-ra60f-swap-to-rc62f.701237/page-7

He had a few pictures posted , but the transmission tail housing was covered with a glove hehe .

 

the cruncher comes through again!

 

I was on that form for about 10 min and just came across this pic, on mine it seems like it almost has a machined groove where the o ring sits but this one is flat if you understand what I'm saying. I'll give the dealer a call tomorrow and see if they can locate such a thing. Greatly appreciate the help I'll let you know what happens

 

You sure that's the right o-ring? It looks like it's too big, it's not in the groove like it should be.

 

Hopefully that's not a part of the case that's worn down. If it is then hopefully someone makes a redi-sleeve. If no one does then you may be able to get a CAT o-ring that's a bit thicker that'll seal everything up

 

That was the old one before I replaced it, the new one sits snug, but good eye!

 

Ah ok I was looking at that first picture going that can't be right.

 

So just the o ring was replaced ?
You could pop the bolts off that cover and feel how hard that metal clad seal is . Look for cracks in the seal . Is the garter spring still inside the seal ? Kinda hard to tell from the pic

 

Any movement on the transfer case input shaft ?

 

When I had it out I didn't feel anything but then again I wasn't looking for it, and with that metal clad seal I figured if it was leaking it would be just going into the trans and not make an external leak but I did clean it off, it didn't feel brittle when I was moving it around and the spring was still intact/in place

 

May want to address that cracked vent hose while your there too

 

Now your being picky eh? XD I did trim it the first time I had it out so all good now!

I do have this exploded parts diagram any idea what the rest of the part number would be for that rear plate? (33102E)

 

Well if you get water in the transfer case or actuator you will have bigger problems than a leak