I know there are at least 10 different breather threads out there. I wasn't sure if I should add this write up to those or create an entirely new one as the method I used hasn't been widely discussed, maybe for good reason?

Utilizing the ARB kit you are supplied with 8 meters (26 ft) of 8mm flexible tubing as well as the manifold which will facilitate 4 separate connections. From there you are left to attach whatever you choose.

There is much attention devoted to the rear diff breather (for good reason) as the one way valve is positioned directly on top of the diff leaving no room for error in any kind of water fording.

I figured since I was going to be under the truck for a while planning this out and had already spent the ~$80 for the kit, why not utilize it to its maximum potential?

So I began hunting down the other 6 breathers for the truck: Rear E-Locker, Transmission, Transfer Case (2), Front Diff, and Power Steering. Without much effort at all I was able to locate them with the rear E-locker being just above the axle, mounted to a crossmember. (Pics to follow) The transmission and transfer case were sandwiched between the firewall and rear of the engine block, roughly halfway up said firewall. They are tucked in nice and tight, and for what its worth, they seem to be in a safe enough location (if you go that deep you may as well be wearing a captains hat as your truck will transform into a submarine). The front diff vents are just below the fuse block in the engine bay. Still, my OCD tells me to consolidate because the ARB breather would look so very under utilized with only one hose routing to it.

So I began pulling breathers off to find the I.D. (inside diameter) of each respective breather hose and they are as follows. Rear E-Locker- 1/8", Both vent lines to the transfer case- 1/8", Transmission- 5/16", Of the two lines routing to the front diff, one was 1/8" and the other was 5/16".

With all of that said, we have 7 breathers to tie into 4 ports.... Lets consolidate.

Within about an hour or so of googling "barb" fittings and looking at materials such as HDPE, Nylon, and Polyethylene, the consensus was Polyethylene would hold up best against the elements and the hose from ARB was made from the same material. So I began searching for reducing couplers such that the same diameter tubing could be used across the entire system. Now that the reducers were sorted, a series of tee's and crosses need to be used to join multiple lines into a single line. After all, the only material being vented through these tubes is air, and since the tubing is 8mm vs the factory 6mm I am ASSUMING the increased diameter will be able to handle the workload of multiple lines.

As soon as I have the fittings in my possession, I will document and complete the install, but thus far this is what I have compiled.

ARB Breather Kit



Rear Diff Breather



Rear E-Locker Breather



Transmission and Transfer Case Breathers



Front Diff and Power Steering Breathers



Parts list to tie it all together



Assuming all of this ties together correctly, it will only utilize 3 of the 4 available ports on the ARB manifold. However, if you prefer to keep all components that use different fluid separate, then 4 of 4 will be used and different connectors will be needed.(Front & Rear Diff w/ E Locker, Transfer Case, Transmission, Power Steering). Not too shabby.

@lmturne1 Can't wait to see pics of it all tied together!

Fittings will arrive tomorrow. I should have the video posted sometime this week, no later than the weekend.

Been crazy busy with many installs this past week. Snorkel, TRD Cold Air Intake, Air Compressor, Shrockworks Windshield Washer Reservoir, Diff Breathers.... It has been a race against the clock to get them all in and the truck drivable. I will have the time available this weekend to post pictures of the completed install.

Any update on this? Also, do you have any links to the fittings you're using rather than a picture off of Amazon?

After such a great start it would be great to see this run it's course and conclude but thanks for the idea and leg work at least.

I also would love to hear about how this worked out in the end.

I have routed the rear diff breather and e-locker breather into the engine compartment using the ARB kit. I'm curious if the front diff needs a free-flowing breather or not.

I thought that the whole point of a diff breather was to eliminate the vacuum in the diff when plunging a hot diff into deep water so as not to suck water into the diff through the axle seals. Since the breather for the front diff is a one-way valve, my understanding is that the valve would close under a negative pressure in the front diff thereby causing a vacuum. So, to me, a free-flowing breather like the ARB kit would still be necessary in the front.

However, I keep reading threads that state that a front breather isn't necessary because the breathers are already mounted in the compartment... but to me the issue was never the height of the breather, but the fact that it was one-way.

I've seen some people put small lawnmower filters on the front breather, but I'd really like to tie into the ARB kit if possible.

Thanks all! I couldn't have done the read without the excellent information in this forum

The front diff does have a 2-way breather on the firewall if I'm not mistaken? Someone please correct if wrong, maybe it's the transmission breather...

I have a 2018 SR5. I noticed that there are only two lines terminating in caps next to the fuse box. This should be the transmission and transfer case breathers.

However, the pic in this thread shows three lines ending there. Why do I only have two? Did I get ripped off? LOL

Dang I wish I could confirm this.

My 2023 TRD only had two lines ending by the fuse box. From some research I've found that the larger OD line is the front diff breather, the smaller OD line is for the front diff actuator.

This thread inspired me to embark on my own journey of tying breathers together to one source. Using the ARB Breather kit. Thought i'd post some photos of the finished product.



Two fuse box breathers. Larger OD line is the front diff breather. Smaller OD line is the front diff actuator breather. Routed these forward past the battery, in front of the radiator, back into the engine compartment and into the ARB Breather assembly. Routed these two lines separately. One in theory could combine them into one line and use less of the ARB breather ports.



routing out of engine bay by the battery.



routing back into engine bay and into the ARB Breather assembly.



Breather assembly from the side. Left two lines are front diff lines. Single right side line is the rear diff breather. This rear diff breather line also has the rear locker breather line tapped into it.



rear diff line with rear locker line T'd into it.



rubber tube is the rear locker breather line. Showing connection into ARB 8mm hose.

Fairly painless to do surprisingly. Hardest thing was figuring out all the inner hose diameters and the best way of securing/clamping the hoses together. Happy to try and answer any questions folks might have.

Thanks!


welp... can't seem to get the photos to post. hmm