Transfer Case wet with oil

Hey, first post! Just picked up a 2015 TRD Sport (auto) a couple days ago. 60,000km on it, didn't get maintenance records so I'm making sure it's all caught up. Did sparkplugs, air filter, oil + filter, cabin filter, and lubricated all the points on the propeller shaft. Still have more to do but while I was underneath I noticed the transfer case has a light film of oil on it. I wiped it up yesterday and have put on some km since, went under today and didn't see any fresh oil, maybe 4x4 will cause more leakage?

The leak appears to be where the transfer case mounts to the transmission, atleast that's what I think I'm looking at (this is my first truck). I didn't see any other oil anywhere, I looked around the oil pan and the rest of the transmission.

I've spent a few hours reading and searching on the forum but don't believe I've seen anyone else with a leak here. What am I looking at for a repair? Definitely going to keep an eye on it but the leak seems very minor, no signs of oil dripping. Wouldn't mind being proactive and fixing before it becomes a bigger issue.

I read to check that the breather isn't clogged. I found lots of contradicting information on where the breather is for the transfer case. I tried to follow it underneath but it's very hard to do. I was able to successfully follow the front diff breather to the engine bay on the driver side. It runs along with a second breather which is a bigger vacuum line. Am I correct that the automatic transmission and transfer case common at some point, and this larger line is the breather for both? Pulled the breathers off and they function correctly. I can blow air out and the check valve prevents air from going in.

Planning to put fresh front & rear diff fluid and transfer case fluid in as well in the near future.

 

Check the torque on the mounting bolts. Check the fluid level and keep an eye on it. If it's slow leak, you can keep up with it by adding a little every couple of weeks. I wouldn't sweat it overly much. If it's losing a lot of fluid, then I would consider having it repaired.
You will get other opinions on this, but remember, a little oil goes a long way when you have a leak like that.

 

Tranny rear main seal.

 

Any idea on torque spec? Probably can't get a torque wrench on most of them anyways but I'll give them a check. I ordered a Haynes manual online but still waiting for it. Am I correct that this would be transmission fluid, not transfer case fluid? Too bad there is no dipstick for the tranny on these.

 

Would this also be referred to as the transmission output shaft seal?

This baby?
https://parts.toyota.com/p/Toyota__...ON-EXTENSION-HOUSING/66840735/90311A0031.html

 

I believe so. If it doesn't get too bad live with it but it won't get better. Unusual for such low miles. Probably could get someone to do it for $1k in labor.