Diff breathers

[Clark Kent]

To mount breathers to the transmission and transfer case, it's major. Removing the tailshaft to then remove the transfer case. My transfer case front seal requires replacing a slow leak (under warranty), actually in a fortnight. Yes I have a July 2023 build. Must drive 900 kms to get it done as it's the closest accredited dealer mechanic.

I am told to get to the gearbox, you disassemble the shifter, remove all those covers maybe one seat to get to it. Yes it's major.

Yep, more trouble than it's worth.

 

[HereinDaRockies]

Why do people think aftermarket breather is needed? The axel was designed to not require an after market breather.

because agile said you should get one?

 

[landmannnn]

Why do people think aftermarket breather is needed? The axel was designed to not require an after market breather.

because agile said you should get one?

Virtually every solid axle has a one way breather, be it Jeep, Nissan, Toyota, Landrover etc.

Quoting from 2023...

IThe problem is that these types of one way valves are good at releasing pressure, but if you drive a hot diff and axle into cold water, the pressure is going to suddenly drop, this will slam the valve closed on the breather and stop any water getting in through the breather, all good, but now you effectively have a vacuum and it will try to equalise itself however it can and that is generally through axle seals etc. probably less of a problem when the vehicle is new, but as it ages and wears the more likely that will happen while in the water and then water in the oil leads to premature and excess wear and corrosion.

 

[Clark Kent]

Why do people think aftermarket breather is needed? The axel was designed to not require an after market breather.

because agile said you should get one?

Virtually every solid axle has a one way breather, be it Jeep, Nissan, Toyota, Landrover etc.

Quoting from 2023...

It's nothing to do with Agile.

If you read through the thread you'll see the interest in fitting an aftermarket breather kit started after a run of reports of pinion seal failures. Related or not, eliminating the positive pressure from the breather (0.5bar, 3.6psi) will reduce the oil pressure against the input seal and stop or slow the flow.

Atmospheric breathers are a well understood solution to vent axle housings. Raising them above the wading line adds some protection when a hot axle is plunged into cold water.
This is what the guy at Air Parts Australia (APA) had to say when I sent him the info on the factory breather:
"...it’s a one way valve to stop over pressure when expanding but would create a strong negative environment when rapid cooling occurs"
As he pointed out in a phone call, air is not going to return through the factory breather but it must get in somehow. If a breather is blocked, or it's a one-way valve, air is normally drawn in through the lip seals which might be underwater at the time.
Same as And3rew said in his earlier post.