Transfer case leak

Guitarguy

TJ Enthusiast
Joined
Sep 21, 2019
Messages
126
Location
Kansas City
Hey guys, I've got an 06 TJ with the 2.4 and 6 speed manual. It's had a minor transfer case leak for awhile now but it's recently gotten pretty bad. It seems like it's coming from the seal in the middle of the transfer case unfortunately, not the end. I'm not sure how much longer the t-case has before it's out of fluid and blows up on me and I don't see any way to check the fluid level. Do you guys think it's worth having someone go through it and replace the seals or should I just find a used transfer case on Craigslist or something and be done with the old one? There's one not far from me from a YJ for $200. I'm pretty comfortable replacing the whole transfer case myself but idk if I wanna dig into the case itself so if I go with having someone fix the current one, I'm having a shop do it. Thanks guys!
 
Here's a pic of the current one as it sits. Also I forgot to ask in the original post, will a np231j from a YJ fit on a NSG370 transmission or does the new t-case have to be from an 05 or 06 TJ?

15943085557106542982524175125477.jpg
 
Hey guys, I've got an 06 TJ with the 2.4 and 6 speed manual. It's had a minor transfer case leak for awhile now but it's recently gotten pretty bad. It seems like it's coming from the seal in the middle of the transfer case unfortunately, not the end. I'm not sure how much longer the t-case has before it's out of fluid and blows up on me and I don't see any way to check the fluid level. Do you guys think it's worth having someone go through it and replace the seals or should I just find a used transfer case on Craigslist or something and be done with the old one? There's one not far from me from a YJ for $200. I'm pretty comfortable replacing the whole transfer case myself but idk if I wanna dig into the case itself so if I go with having someone fix the current one, I'm having a shop do it. Thanks guys!

Here is a pic showing the drain and fill outlets.

NP 231.jpg
 
I doubt it. I've only had it for a year but when I got it, it had 31s on it and the speedometer was reading about 5mph slower than I was actually going. Went back to stock tires and rims to help the little 2.4 on hills and it read spot on accurate again. So whoever put the 31s on it didn't bother to change the gear for that and I doubt it was changed out before that.
 
I will say the front half of the transfer case is bone dry but from the seal in the middle all the way to the back of the case is pretty soaked.
 
Clean it up, top it off, and keep an eye on it to determine where the leak is coming from. Someone once mentioned using baby power to find a leak on their tcase
 
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That's pretty smart! So coat the transfer case with baby powder, drive it around a bit, and wherever it's stuck on is where the leak is?
 
That is the gist of it. Clean it up, cover it with power and go for a spin
 
Dang I never would've thought of that. I've cleaned it up before but there's oil all over not too long after and I'm back to square 1. Thanks for the tip!
 
Oh also, it looks like regular oil coming from the case but it looks like ATF is what you're supposed to use. When I put more fluid in it, what should I use?
 
Any good quality ATF is fine. Based on where it appears to be leaking, even though you're not aware of its speedometer gear having been replaced, I wouldn't be surprised if the o-ring surrounding the speedometer gear housing was nicked or cut and allowing the leak. Mine leaked pretty bad from that.
 
I'm in the middle of cleaning it all up and a few little pieces of the seal half way up the case have come apart. Not near enough to go all the way through the seal but still.
 
Also side note but this thing is CAKED. Just brake cleaner and paper towels isn't getting it down to the metal hardly anywhere.
 
So I couldn't get that baby powder spread too well but I just ran to the store for some ATF, came back and it's got a leak between the yolk housing and the big main part of the t-case. It may have one half way through the case too, I'm not sure.
 
Hopefully y'all can see it in this pic here. There's a run going from that seal to the bottom of the case. It is red though so I think it is ATF in there, not oil so that's good I guess.

15943178565847947792448407062197.jpg
 
Also side note but this thing is CAKED. Just brake cleaner and paper towels isn't getting it down to the metal hardly anywhere.

you'll probably get better results spraying it down with Gunk degreaser or Simple Green, giving it a few minutes to do it's work and then blast it off with a power washer.