Transfer Case Actuator Breather Hose

Hello All,

I've got a 2005 TRD Off Road w/ 6 speed manual transmission. The transfer case actuator breather hose rotted out which led to water getting in and corroding the actuator contacts. I went ahead and replaced the actuator which was surprisingly easy, and now I need to replace this breather hose so it doesn't happen again, and I have a few questions.

Thanks in advance!

Hose:
The current breather hose looks like rubber or silicon and has some kind of plastic wrap around it. I cut a piece off where it extends past the plastic wrap and got a few feet of similar sized generic vacuum hose from autozone. Just wondering if this standard vacuum line will work for this application. Looks like that plastic wrap might be a heat shielding, but I can't imaging the exterior of the transfer case get that hot.

I can't seem to find any info about this hose.

I believe this is the type I got, might be different diameter, just matched the piece I had.

https://www.autozone.com/ignition-t...tal-5-32in-vacuum-hose-sold-per-foot/4942_0_0

Any ideas if this will work? Should I add some kind of shielding?



Routing:
I was planning to reconnect to the new breather hose to the existing nipple located on the side/top of the transfer case. Due to the location, it might be difficult to get the new hose seated properly and I'm wondering if it makes more sense to route it somewhere else.

I can't see much up there, so I am not sure if that extension leads up to the engine bay or not. I've seen some info that suggests that it leads into the transfer case for some reason? I imagine it is just venting because there is just the electrical components inside the actuator housing where the hose connects.

I'm seeing some after market breather kits where people are running the breather hose into their engine bay or behind the taillight? I'm not sure if removing that hose could cause an issue because I've seen somewhere that the hose might vent into the transfer case instead of just venting to the atmosphere.

Should I just route up to the engine bay? If I do that, should I cap off the nipple on the transfer case or is it just an extension?

Does anyone have a diagram for the route?

Transfer Case Actuator Replacement and Timing Note

Just a note about the timing:

I reinstalled the actuator without opening the transfer case and was able to get the timing right on the first try!

I got the vehicle into 2HI (had to turn the vehicle off and on to engage/disengage) before removing the actuator. The new actuator was set somewhere in the middle of the range around the 4HI area. To set the new actuator to 2HI I just connected the two contacts at the end of the plug to a drill battery to drive the motor (switched the +/- to reverse) until the shaft was fully extended and in 2HI position. It worked great and now I can get in and out of 4HI and 4LO.

I saw a video where someone used a pry bar to push the shaft all the way into the transfer case to manually put it into 2HI. I think between that and running the motor to the fully extended position, it could be an easy way to get the actuator timing right.

I have some pictures, so I might do a write up at some point on this process if it would be helpful for anyone.

 

Standard vacuum line will work.
Just keep an eye on it yearly. As the new hoses seem to dry out fast.
Nothing it made like it used to be.....

 

I don't see why regular vacuum line wouldn't work, it just might not last as long as the OEM hose.

As for the routing I believe it goes straight to the transfer case on top.

If you do a writeup on changing the actuator I'll certainly link to it in my 4wd help thread

 

i used vacuum line that i slid inside of some old fuel line sheathing to protect it.
i zip tied some window screen material on the tip, to keep the effing wasps out of it.

don't recall exactly where i ran it. i think up high under the hood because i have been known to ford 2+ ft of water.

 

I used some vacuum line and some stainless steel tubing to splice a new piece on the end. I left about 5" extra so I could trim a little back every year and re-terminate it. A little super glue on the stainless tubing, inside the rubber tubing works well. I then did a little shrink wrap around the splice as well.
I think 99% of the actuator failures are because of this hose splitting and falling off. They should be checked every few months and trimmed accordingly.

 

Good idea! I bought 4 feet from autozone and keep replacing the whole length of breather hose. Thank you winkel

 

during an inspection under my truck found what appears to be original vacuum line to transfer case actuator cracked and fallen off.

I believe 4WD still worked recently before that leading me to believe it is related to a breather.

anyone know a confirmed fix for this?

I may need to take another look to see where it goes and guesstimate how much new vacuum line to buy, and maybe take some measurements with a caliper to get an idea of what hose to order regarding ID OD thickness etc.


would probably lean towards silicone material as that is a common upgrade in the automotive world for a material that looks nicer, still cheap, better, and may last longer

 

Yes, I have some stainless tubing that will just fit into that line. I cut off the bad end, super glue a 2" piece of stainless tubing inside, put a new piece of vacuum tubing on it (reinforced splice), shrink tubed the outside of the splice and then pushed the new tubing onto the breather tube.
It gives me some slack to trim the end every few years, for the next decade or so.
You might want to pull the cover and makes sure there's no water or crap in the contact area.

 

OP, that hose appears to be Toyota part number 90447-08175.

It should come off the actuator and then connect again to a nipple on the side of the transfer case.

 

Questions about this actuator vent hose...

How long roughly is the part?
What ID hose to replace it?
finally, how possible is it to reach in and replace it (seems like getting it to the top of the transfer case is tough?) I may use a spring clamp at both ends.

 

I've replaced this before but already had some and didn't measure it; I'm going to guess it's 3mm, or 1/8". Hose like this is sold by the foot, so just get a foot at NAPA. The OE hose is barely long enough, so add a little extra. The coiled wrap is for abrasion resistance. You may be able to remove the old wrap and install it on the new hose. You don't need a clamp as there's no pressure on the hose- it's a vent. if it makes you feel better, you can install plastic zip ties.

 

Damn its a PITA getting the hose back onto the nipple on top of the transmission. Not much hand space.

But indeed my hose was bad

 

Where are the two other vacuum hoses connected to. I just did a transmission drop to replace clutch etc. I now seem to have a gear oil leak from those locations.

 

Have same problem. Just happened to notice what looked like a small vacuum hose hanging down unattached to anything. Hose had split and fell off. I did see a small nipple on actuator that had nothing connected to it so I’m assuming that’s where the dangling hose goes. Don’t have enough slack in that hose to connect it so I’m gonna get a plastic connector to splice into it and leave plenty of slack so if it happens again I’ll just cut off the split end and slip it back on. Looks like Toyota could have done better than this knowing that vacuum hose is going to split and fall off.