2015 Tacoma 4WD auto - rear transfer case adapter seal help

Hello TacomaWorld,

Last weekend I replaced my front/rear differential and transfer case fluids. While I was under the vehicle I spotted this weeping fluid on the rear tcase adapter sealing surfaces.



From my research on this forum I have learned that this is either ATF or transfer case gear oil because there are 2 seals in play:
1. Rear Transfer Case Adapter Oil Seal, pushed into the transmission case
2. Transfer RH Bearing Retainer Oil Seal

I cannot identify whether the oil is atf or gear oil. Should I purchase and be prepared to replace both seals? I am going to put the truck on flat ground to check the ATF level today.






I watched "Timmy the Toolman" on youtube removing the transfer case out of a 4runner.
https://www.youtube.com/watch?v=oZDSjlxl2Q4

This job is within my skillset but I want to make sure that I have the right ideas, parts and procedures in front of me before I get started.

 

I was locating the parts today and noticed the diagrams reference multiple different "short numbers" but all of them go to the same "long part numbers" as shown belown.

https://parts.toyota.com/a/Toyota_2...SFER-CASE--EXTENSION-HOUSING/674470-3609.html

Transmission Seal
Top picture (in red) shows 36117A or "seal"
9031143007
(Supersession(s): 90311-43007; 90311T0028; 90311T0080)
36102J - links to part above
35015J - links to part above

Bottom picture shows 35015J which links to "seal"
9031143007


Transfer Case Seal
Top picture (in blue) shows "36102L"
"Transfer Case Input Shaft Seal (Right, Front)"
9031143008
Supersession(s): 90311-43008; 90311T0071

Bottom picture shows "36102F" or same part as above

 

Since you have to pull the cases apart to check which one is leaking, I'd just replace both while you're in there. No sense in doing one and making the wrong call on which one was leaking only to do it again. It's most likely the transmission seal, I haven't seen the transfer case input shaft seal leak too often in these trucks.

 

Thanks for the reply. I am going to purchase both just in case but it's very good to hear the tcase one isn't often leaking. This lines up with the fluid quantity that I drained last weekend (a sliver shy of 1qt).

The youtube vid does not make the transfer case pull look too hard and worst case scenario I can let the truck sit in my garage for a couple weeks as I have another to drive around. Hopefully that won't be the case.

I may "dry run" the repair this weekend to make sure I have the proper extensions to get to all the nuts and can identify all the electrical/hoses to the tcase.

 

This X2. Cheers