How can I stop this transfer case leak?

[John’o]

I have a leak on my transfer case. Started leaking at same time SYE drive shaft seal started leaking (kid drove the TJ so I suppose he smacked something hard). The O-ring was munched when I removed and replaced the 1st time. I replaced the O-ring three times.
It leaks with little to no torque,
It leaks with mid-level good-n-tight torque,
And It keeps leaking with Plenty in of torque.
Questions: What is the correct O-ring? Should I get a copper crush washer?
Should I get a new plug?
What is correct torque?
Links for what to get are much appreciated.

 

[John’o]

2002, 2.5L stock Ax-5 transmission and stock transfer case.

 

[OldBuzzard]

Are you using an oil-safe O-ring, or one for water pipes? Is there a burr in the SYE housing, or on the speed sensor?

 

[John’o]

Are you using an oil-safe O-ring, or one for water pipes? Is there a burr in the SYE housing, or on the speed sensor?

Probably a water o-ring. Will assure next one is oil rated. No burs. Did inspection yesterday.

 

[John’o]

Thinking just RTV and done. Should I put it on the treads?

 

[hear]

The speedo sensor is actually 2 pieces, and there's another o-ring on the inner piece...which you don't even realize is a separate part until you do the work. I had a leak in the same spot and it was resolved when I replaced it. This is from a 97 from it's similar on other years.

 

[John’o]

Mia culpa. It is not leaking from the speed sensor. The leak is from this plug. Any idea what it is called?

 

[hear]

oh that's the selector shaft...I've never understood why that was built that way. Yeah, I would just RTV it if you can't make the o-ring not leak.

 

[John’o]

oh that's the selector shaft...I've never understood why that was built that way. Yeah, I would just RTV it if you can't make the o-ring not leak.

Huge thanks. I don’t mind RTVing. I used to work on 40 year old Helos. Just don’t want to do something silly out of ignorance.

 

[John’o]

Huge help as always. Just order Omix-ADA 18676.34 NP231 Selector Shaft Seal, 87-06 Jeep Wrangler https://www.amazon.com/dp/B000FQ0C66/?tag=wranglerorg-20

 

[Vinman]

Also ensure the vent hose isn’t plugged, if it is, it could be pressurizing the case and pushing oil out of the weakest link.

 

[Blackjack]

oh that's the selector shaft...I've never understood why that was built that way. Yeah, I would just RTV it if you can't make the o-ring not leak.

It is for a switch that was used on YJ/XJs.

 

[hear]

It is for a switch that was used on YJ/XJs.

ok, then I've never understood why they needed two different switching mechanisms for what amounts to the identical transfer case.

 

[John’o]

Also ensure the vent hose isn’t plugged, if it is, it could be pressurizing the case and pushing oil out of the weakest link.

Will do. I saw another post about vent hose. Thanks!