Axle Vents

[brazengoat06]

What little Information I'm finding on axle vents seems to suggest that they are some sort of pressure release. Upon inspection they appear to be a primitive one way valve that wouldn't be very effective. Was thinking about relocating my vents to a higher location and wanted everyone else's thoughts. Thanks! 84 M923

 

[Swamp Donkey]

I removed mine and ran new hose with breathers up behind the cab for the rears and under the hood for the front.

 

[Artisan]

Simply driving up and down in altitude can create pressure differentials
inside the axle. If this happens it can force out grease or if hot and
you ford, thus coolong things, if can create a suction...

Very best set up is to simply extend
them to well above any water level you might encounter.

IMO


PS, don't forget about your flywheel housing plug that is stowed under there
that you are supposed to install BEFORE fording.

 

[Csm Davis]

Do a search on fording kit

 

[rhurey]

I relocate them to the cab. Regulator and gauge to be able to pressurize is on "wish list"

(strangely, the extended fam always asking for gift ideas went from "we don't want to buy gun stuff" to "we don't want to buy truck stuff")

 

[JohnnyBM931A2]

I relocate them to the cab. Regulator and gauge to be able to pressurize is on "wish list"

(strangely, the extended fam always asking for gift ideas went from "we don't want to buy gun stuff" to "we don't want to buy truck stuff")

lol.. That sucks

Relocating them sounds like a good idea. I think I will have to add that to my "To Do" list.

 

[BigDawg41]

What little Information I'm finding on axle vents seems to suggest that they are some sort of pressure release. Upon inspection they appear to be a primitive one way valve that wouldn't be very effective. Was thinking about relocating my vents to a higher location and wanted everyone else's thoughts. Thanks! 84 M923

So you're saying it's normal for the axles to build some pressure internally before its vented? Whenever I check my axles they always have slight pressure in them when removing the fill plug.I thought the vents might be plugged and was going to remove and clean them.

 

[mcmullag]

If you look at a jeep wrangler, I think they started quite awhile back running a hose up from the axle and transmission up to the engine firewall with a vent at the end of the hose.

 

[73m819]

Put a cheap in line gas filter at the end of the vent hose with the open end of the filter turned down, this will keep dust and water from being drawn in when the axle breaths.

 

[brazengoat06]

Thanks for all the good advice! I'm still not quite on board with the whole pressurized axle thing. Not to be argumentative but in all automotive applications there is zero pressure allowed to build or else a leak will form. When I replaced my trucks axle seals I didn't really notice anything different about the design that would allow it to hold pressure without leaking. Can anyone explain? Thanks

 

[tobyS]

A sintered pneumatic muffler-breather came to mind.

 

[rhurey]

The pressurize was meant as an on demand when in water to help keep the water out. Not to run around in normally.

 

[brazengoat06]

ok so took my axle vent off to mod and sure enough pressure came out of axle... so just to make sure vent wasn't plug I ran shop air through it. you can hear a check ball inside. so all in all it is a pressure check valve of sorts, so for me I will "insert foot in mouth"

Now for the mod it seems a bit pointless to execute as long as all your seal, boots, and vents are in good working order. This is unless you plan to be submerged for a long time then maybe you would have a problem, but even then I would be skeptical. Anybody else have input on this?

 

[bchauvette]

I plumbed all my together with nylon tube up the intake stack finishing in a 90 deg turn looking down. Be sure to leave enough slack for axle movement.

 

[Swamp Donkey]

I used vacuum line and a facet filter. I had a bunch of the line left over from another project.

 

[73m819]

ok so took my axle vent off to mod and sure enough pressure came out of axle... so just to make sure vent wasn't plug I ran shop air through it. you can hear a check ball inside. so all in all it is a pressure check valve of sorts, so for me I will "insert foot in mouth"

Now for the mod it seems a bit pointless to execute as long as all your seal, boots, and vents are in good working order. This is unless you plan to be submerged for a long time then maybe you would have a problem, but even then I would be skeptical. Anybody else have input on this?

WRONG about the MOD being POINTLESS, the axle vent ONLY breathes one way "out", as pressure builds and the vent is SUPPOSED to dump the extra pressure, it dumps the pressure, then the axle cools down, the pressure drops, to where there COULD be a bit of vacuum, this will tend to draw dust, ect to/through the seal, no different then a constant pressure on the seal that will tend to try to force oil out, oil and dust = valve grind compound or in this case seal wear. the HOT pressurized vented air is oily, it makes the axle vent oily, which in turn dust sticks to, so in time it takes MORE pressure to pop the axle vent, holding more pressure in the axle, and in time, things only get worse, NOT BETTER.

Unless you only ran a few pounds (10 or less, more like 5) of air to test the vents, YOU WASTED your time and shop air.

The axle vent on our trucks is there fore ONE REASON and ONLY one reason, that is for amphibious operation, to help keeping water out of the rears, this is the same reason for the rear grease hubs.

 

[brazengoat06]

WRONG about the MOD being POINTLESS, the axle vent ONLY breathes one way "out", as pressure builds and the vent is SUPPOSED to dump the extra pressure, it dumps the pressure, then the axle cools down, the pressure drops, to where there COULD be a bit of vacuum, this will tend to draw dust, ect to/through the seal, no different then a constant pressure on the seal that will tend to try to force oil out, oil and dust = valve grind compound or in this case seal wear. the HOT pressurized vented air is oily, it makes the axle vent oily, which in turn dust sticks to, so in time it takes MORE pressure to pop the axle vent, holding more pressure in the axle, and in time, things only get worse, NOT BETTER.

Unless you only ran a few pounds (10 or less, more like 5) of air to test the vents, YOU WASTED your time and shop air.

The axle vent on our trucks is there fore ONE REASON and ONLY one reason, that is for amphibious operation, to help keeping water out of the rears, this is the same reason for the rear grease hubs.

I think your confused, my useless comment was made towards the vent MOD not the vent itself. Of course the vent has a use. As for vacuum, likely what will happen is it will draw in air from the void in the knuckle which is clean and dry, assuming one hasn't crammed it full of grease.

 

[73m819]

I think your confused, my useless comment was made towards the vent MOD not the vent itself. Of course the vent has a use. As for vacuum, likely what will happen is it will draw in air from the void in the knuckle which is clean and dry, assuming one hasn't crammed it full of grease.

ALL the axles have axle vents, on the front, air will be drawn in through the axle seal, oil out, the grease will be no where near it, also while we are on "axle" vents, the transfer case has the SAME vent as well as the manual transmission, these ALSO have the SAME issues as the axle vents.

The "VENT MOD" is due to the VENT issues, there would be no need if there were not the vent issues, the number ONE cause of axle, and to a lesser extent transmission/transfer seal leakage is a BAD vent.

As the OLD and SORTA WISE Wreckerman would say "your dog, beat it as you see fit"

 

[JohnnyBM931A2]

ALL the axles have axle vents, on the front, air will be drawn in through the axle seal, oil out, the grease will be no where near it, also while we are on "axle" vents, the transfer case has the SAME vent as well as the manual transmission, these ALSO have the SAME issues as the axle vents.

The "VENT MOD" is due to the VENT issues, there would be no need if there were not the vent issues, the number ONE cause of axle, and to a lesser extent transmission/transfer seal leakage is a BAD vent.

As the OLD and SORTA WISE Wreckerman would say "your dog, beat it as you see fit"

Good point about the transfer case.. I wasn't even thinking about that. Would be kind of dumb to take the time to extend the vents on the axles, only to leave the transfer case stock. So I would need to run 4 vent lines up above the "water line," instead of 3. Good to know

 

[tobyS]

This thread seems to have moved from a properly functioning vent to mods for fording. Is mudding and being under water your use or having a working vent? Venting goes both ways, so why a check?