Tranny, T-case, diff vent valves

[ParadiseMJ]

So, I went on the search for the little plastic vent tips for the AW4, the T-case, and the front diff.  I read that "any" parts place would have them in the Help! section...but no joy...at O'Reillys and AZ no luck, so I went to NAPA, where they have BOOKS.  The computer said transmission case vent, but nothing came up for Jeep.  So after looking for 10 minutes the guy got out the book and went right to the page that had GM tranny vent valves.  The look the same, they say 3/8".

 

My question(s)

 

1.) Other than keeping out water and other crap, what do the valves do...and are they necessary other than that.

 

2.) My vent hoses are 3/8", the GM valve fittings are 3/8".  Is there a reason the GM valves will NOT work or are they just that generic and why isn't anything listed for Jeep.

[daking]

The concept is that as the oil in the diffs, T case and transmission heat up, it expands. That expansion displaces the air in those items. The vent tube allows the air to escape, and come back in as it cools. The cap is basically like a "U" shape to help limit bad things like dirt or dust from going down the pipe. 

 

You want to insure the vent pipes are higher then any water crossing you may experience. most are at least the height of the intake. It is important to make sure the expanding air has a free flow. A clogged or restricted vent will cause premature seal failure, as the air will push out of the next easiest spot, a seal. 

 

There are a few other solutions other then the cheap factory solution.

 

You can buy "Billows" for example. They look kinda like a mini shock boot, but only have one hole. The fit over the hose fitting of the diff, T-case or Trans. My issue with these is, I think they can fall off. I have no personal experience though.

 

You can simply attach a small filter to the end, even a fuel filter. Some guys make a "loop" in the hose to limit water ingestion. But, most guys know they own a Jeep, not a boat and there for don't enter deep water.

 

What I did was connect all 3 front lines (Front diff, T-Case and Trans) to a block. Then connected a breather type air filter, and mounted high on the firewall. As such:

 

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[ParadiseMJ]

So, I went on the search for the little plastic vent tips for the AW4, the T-case, and the front diff.  I read that "any" parts place would have them in the Help! section...but no joy...at O'Reillys and AZ no luck, so I went to NAPA, where they have BOOKS.  The computer said transmission case vent, but nothing came up for Jeep.  So after looking for 10 minutes the guy got out the book and went right to the page that had GM tranny vent valves.  The look the same, they say 3/8".

 

My question(s)

 

1.) Other than keeping out water and other crap, what do the valves do...and are they necessary other than that.

 

2.) My vent hoses are 3/8", the GM valve fittings are 3/8".  Is there a reason the GM valves will NOT work or are they just that generic and why isn't anything listed for Jeep.

 

That's a nice clean set-up and will likely outlive the Jeep itself.  I'm just planning on replacing what was there...the $3.99 route.  Thanks

[cruiser54]

You just need the white plastic pieces?

[ParadiseMJ]

Yep, I got them at NAPA...$3.99... :thumbsup: