4WD actuator/ transfer case issue?

So my transfer case actuator recently went out on me, it corroded on the inside. Broke it trying to get the cover off. I bought a new one, installed it and it worked great. I ended up sliding into a ditch on a dirt road and the transmission crossmember hit a rock hard enough to jerk the truck a bit and dent the crossmember a bit. The crossmember is fine but shortly after I noticed that there was oil leaking. I went under and had a look and it was from where the cover for the little gear access on the actuator was. So I thought no problem I’ll just reseal it and it will be fine. Well I sealed it up with rtv and it was fine. I started checking it daily, when I left, when I got to work, before leaving work and when I got home, about a 10 minute ride. 2 days later I noticed it was leaking again but it was much slower. It started leaking from where the buttons screw in at the top of the actuator. So I tightened those up because they weren’t very tight from the factory. Now I went for a ride and checked it again and this time I can’t figure out where it’s coming from. I thought there was pressure building up somewhere and forcing it out so I started poking around and if I drive it and then unplug the breather hose air hisses out. I have verified that the hose is clear, I can blow air with my mouth into the transfercase and into the actuator though the breather hose. Idk what is going on at this point. It’s still slowly leaking and pressure seems to be pushing it out. I have been making sure the transfer case is being maintained and staying relatively full. 4WD still works fine too. Google wasn’t helpful so now I’m here.

 

Got pics, so we can sorta see the overall damage and speculate what issues that damage maybe caused?

Does the fluid draining out stain a towel brown? Does it smell rank, like gear oil, or more like petrol/motor oil?

 

It’s definitely gear oil, it’s slight brown and it smells like gear oil. I have also had to top off the transfer case every few days. Is there a breather on the transfercase that could be clogged that’s causing preasure to build up and force oil out of the weakest seals like the ones on the actuator? Because if I unplug the breather on the actuator it doesn’t leak anymore. I also noticed today when I cracked the fill plug there was a little hiss but not much, I had only driven it up and down my street a few times. I am unable to take pictures at this time.

 

@FiatRunner, you got any thoughts on this? I'm trying to think through what would cause the transfer case to leak gear oil into the actuator. But I haven't had my actuator off (good video of it lives on here, I'll edit with it if I can find again). I recall there's a pushrod on the actuator that's notched and keys in with the transfer case, so certainly there's some fluid pass-thru possible.

@Avery-1227 did you confirm the transfer case itself isn't cracked, and the actuator body isn't cracked also, and none of the fasteners holding the actuator down are gone?

 

Nothing is cracked, 4WD still works just fine there’s just pressure building in the system forcing oil out, I fix one leak and another one shows up in a different spot on the actuator. I heard there was problems with the 4Runners transfer-case where the breather gets clogged and then you blow out driveshaft seals. I was wondering if something like that is happening to me where instead of driveshaft seals its actuator seals because they are the weakest. But I couldn’t find anything on a breather for my transfer case.

 

Get them uploaded when you can. Pictures really do help

 

We like pics, like a lot….

 

Yeah, I don't see how we can remotely help resolve this issue without pictures. It's pretty much impossible, can't even begin to guess where fluid transfer is happening, or guess what a whack to the x-member would've done without seeing the damage caused to the x-member, so one could speculate about what the force/direction could've impacted.

I can't find anything in the 4WD diagnostics thread on that video, makes me sad. But in the 4th video of the diag thread, where they're replacing the actuator "in under 10 minutes", the only place I see where gear oil could possibly exit the TC is at the boss/hole for the engagement shaft (blue arrow). Something would have to happen for fluid to be able to burp up into the actuator housing itself. I also notice there appears to be an o-ring (red arrow) that could leak.

But we also know the transfer case is aluminum, and cracks easy as hell, and the fill/drain plugs will strip out if you so much as look at them wrong. So my suspicion is, something is cracked on the case itself. Without pics, I don't see how we can tell.

​

 

FSM section TR page 3 (page 2354)

 

I haven’t seen anything before about fluid being pushed out of the TC or the actuator. That said, we’ve seen rear differentials get hot and push fluid out before, due to a plugged breather. What makes this different?


I’d start by simply checking the breather for the TC. Both the TC and front diff breathers are mounted on the drivers side inner fender, down low in the engine bay. I would check to make sure these aren’t rusty or plugged with dirt/gunk. Then I would take photos and post them here.

 

@BubbaW outlines breather locations here, in the engine bay, mounted to the framerail, between the oil dipstick and brake booster. https://www.tundras.com/threads/2005-tunda-dc-4x4.158687/#post-3928509

But I still fail to fathom why the dripping would happen after (specifically) a hit to the tranny crossmember OP mentioned. Unless the dripping was happening prior and OP failed to notice it.

 

So, my original actuator cover was cracked, so pressure was being relived. I think when I installed the new one it had no where to go since the cover was new and not cracked. And I had only noticed it when I went under to check if everything was good after hitting the crossmember. So it probably was leaking before I hit the crossmember.

another note I looked at the breathers and the one with the bigger hose was clear I could blow air though it just fine but the one that has the smaller hose was completely clogged I could not blow any air though it. I took it out completely and went for about a 30 minute drive and it still leaked and air still hissed out when I unplugged the actuator breather. Could the line going from the tc to the breather be clogged. Would it be a good idea to unplug the actuator breather and blow some air down the tc breather line to see if it comes out the other end?

 

Wanna know if the line is clogged? Detatch at both ends and blow through it. Ideally from the top, unless you like gear oil in your mouth.

Understand something: It's normal for some pressure to build up, but it shouldn't be positive pressure, it should be negative pressure (i.e. VACUUM). Most breathers are one-way valves, on purpose: You want hot air to have a way to escape, but you DO NOT want humid air or water or outside elements like dust and dirt to get into the diff/tc.

Thinking about this logically, what happens when hot gasses buildup inside the TC? Expansion, and thus off-gassing out the valve. What happens when those hot gasses inside the tc or diff cool? Contraction, thus creating mild vacuum inside the chamber.

Probably see this most notably with the rear diff breather, you probably should be changing that every 60k-80k miles (since blowing out a rear wheel seal/bearing is fucking awful to deal with in these trucks and the $3-4 breather is small in comparison, and with diff juice changes on the standard schedule of 30k miles if using full syn, every other change is about right, unless you're towing, in which case you should change twice as often). Any time you pop off that breather while the truck is cool, you'll get a hissing noise from the joint sucking in outside air.

 

Yea I understand how it’s supposed to work.

I got my my air compressor out set it to a low psi and tried blowing some air down the tube at the breather side it hissed for about a second then stopped when I took the nozzle off air came back out of the breather so it’s seems like the line is clogged. Either way I blow air in it always comes out the end I blow it in weather i blow it on the actuator side or the breather side.

 

You can never be too sure on the internet what people know or don't know, so I'll always take the extra keypresses to explain it. If nothing else, sometimes it gets people thinking in 'deductive logic' mode, bigger picture, and that's what's needed.

I'm not sure if Toyota sells that line as a replacement part or as generic hose. Can look it up later if you want.

Else, any oil-tolerant hose with the same OD and ID will likely suffice on replacement.

 

I don't know if @Avery-1227 has an RC, AC or DC or if 5VZ or 2UZ, but assuming 03 AC 2UZ 4WD, I found this:
Hose Sub-Assembly, Transfer Breather
P/N 36407-35030

 

He’s keeping that a secret but it is Green if that helps

 

It’s a 4.7 v8 access cab sr5 4WD.

I just did some digging and those two breathers by the inner fender go to the front actuator and the front diff, so the transfer case breather still needs to be found.

 

Besides the 2 in the post @shifty` linked to up above, there are 2 more.

 

Shifty made you aware of that in post #11

See post #16

 

That is not there on mine I do not have those in my engine bay. I was just looking around online and I found a picture of what mine is like. Could what I circled in red be the breather? There are no other hoses on my transfercase but the one that goes from the side to the Actuator and the u shaped one on top.