Diff breather thoughts...

[Bussa]

Hi guys

Was looking to buy a diff breather kit for the Fortuner and was asking around about what to get etc. I am getting mixed messages as to whether they are required.

Apparently the new Toyota 4x4s (Hilux/Fortuner/Landcruiser variants) have very good diff breathers which will withstand being submerged for brief periods, i.e. river crossing.

Has anyone else heard any info on whether a diff breather is actually required for the odd river crossing in these models?

Cheers

Josh

[Skardo22]

I guess it depends on how deep a crossing you want to do and the fording depth of the factory breathers? I haven't checked where the factory diff breathers are or what the fording depth is, but my guess is if your planning on crossing a river that is over the factory recommended fording depth of the vehicle, then i would be extending the breathers and fitting a snorkel.

If you do find out any further info on this, I'm sure plenty of members would like to know. myself included.

[geo]

Toyota quote 700 mm as the fording depth for the Fortuner.

[Skardo22]

i would recommend extended diff breathers and snorkel for any river/water crossing over the 700mm

[lufkin]

I had to run cabling under my car yesterday so thought i would check diff breathers. This is the rear breather directly on top of diff

[kzen]

Does anyone know if the valves at the end of the breathers are all one way valves? Just curious as to how these would help when the diffs are cooled rapidly... they won't help to equalise the pressure. I've seen two in the engine bay (next to the battery).

Assuming one for the front diff. Haven't crawled under to see where the other one leads... assuming it's the Auto disconnecting differential as per other forum posts but not sure. So what about the manual transmission and the transfer case?Sounds like we need a total of five breathers in the manual (not sure about the auto).

[Bussa]

There are three breathers at the firewall in engine bay at back of engine - front diff, transfer case and gearbox. I had no idea about the ones near the battery....I am only going to extend the rear which is placed on the diff itself. Midway up the engine bay for the remainder are fine. You have other issues if you are wading water that deep in a Fortuner :S

Should mention this is an auto....unsure on manual

[lufkin]

My brother in law has his own workshop and also has the new hilux + 200 series. He tells me they are the same and are one way valves and when dropping oil from these diffs it is noisy as by the time it comes to service they are under a massive vacuum

[Bussa]

Interesting that they appear to be one way...i am not sure this is accurate. The diff must let air in when the diff cools to equalise pressure, otherwise this pressure would eventually force oil out of the diff seals?

[kzen]

Might be the reason most people replace them valves with a filter of some sort.

[Bussa]

Hi guys

I have extended the rear diff breather to the engine bay. Easy job. I spoke with a mechanic at Toyota when I had the 1000km check up. He stated the Fottuner, like the Prado 150 and new Hilux run the front diff, gear box and transfer case breather half way up firewall on engine bay and are relatively safe, so don't need extending, unless you plan on wading through water that is deeper than your bonnet. I don't plan on doing this...!

Cheers

Josh

[4Tuner]

I have extended the rear diff breather to the engine bay. Easy job.

i'd be keen to do this also. Any further tips/pictures on how you did it would be really appreciated. Did you buy a kit of some form? Thanks.

[Bussa]

I purchased a kit off eBay - prices vary greatly. Basically you can buy a named brand and pay through the nose, or go middle of the road and get the same materials with no branding for a quarter of the price (my choice!) No issues as yet.

I ran the tubing along the left side of the undercarriage (when looking at car from the behind) and fed the tube up through the engine bay and mounted the end in the far top right corner of the engine bay (when looking from front of car). Is an easy job, takes about 30 mins to crawl under and feed the cable along. I affixed the tubing with cable ties

Tips:

- dont affix tightly until both ends of tubing are in position;
- ensure you have some slack on the diff end to allow diff articulation. Otherwise you run the risk of the breather hose ripping from the diff if it doesn't have any flexibility.
- keep tubing away from exhaust and manifold

Cheers

Josh

[chesty]

From my understanding; The breathers are designed to allow air pressure to escape as the diff, gearbox etc..as it heats up. When the diff takes a bath the valve (breather) closes to stop sucking water as the diff cools. The issue with this is that the diff then has a vacuum and wants to suck from other places which may mean through oil seals. By changing the breathers to allow equalization of pressure (i.e. no valve), and mounting up higher, helps mitigate the issue of water in the diff etc... It's a good little project to set them up.

[4Tuner]

Thanks for the tips Bussa which helped.

i finally got around to it.

im no genuis on car mechanics but was easy even for me.

fitted the ARB kit to the rear (as per previous comments the front diff is one of the two breathers already in the engine bay - is that confirmed?)

[Bussa]

Nice work!

[Eastie]

This might be of some help. Not mine, but found it for the hilux when looking for info: https://www.dropbox.com/s/ahmujid7pl...Guide.pdf?dl=0

[borgna]

hi so thanks for the guide its great. I have a question. reading that its saying there will be 6 breathers in total. I purchased an arm diff breather kit which can only hold 4 so does this mean i would have to buy another one to hold all 6 which would be the best possible option or are these "actuators" not really important to extend? I'm not sure what they do?

[borgna]

p.s ill be planning on doing the tele track thats why I'm thinking it might be worth raising them all that little bit higher aswell?

[White One]

I just ordered this off ebay -
https://www.ebay.com.au/itm/HKB6WB-3...4AAOSwA3dYS5d7
the seller said it is specific to the GUN126 Hilux and includes all adaptors to the factory breather hoses. I'll fit it over the next few days and let you know how it goes.