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Extended Diff Breather (Mod)

Featured Replies

Hello All,

 

So while rebuilding my diff I noticed that the breather was pretty much buried in WCSS and Walker Valley mud, even after several washes.  Lots caked up between the drop plate and diff cover.  This got me thing of extending the breather to not only to keep it from getting covered in mud and filled with water but to help with air exchange when hot.  Have noticed this as being a popular mod on Toyotas and other wheelers so I set out.

 

What I ended up using was a 1/4 pipe barb fitting.  I didn't even need to drill the existing hole as a 1/4-18 tap was a perfect fit.

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After some cleaning and painting I reinstalled the fitting using thread tape and snugged it down tight.  Bought about 6 foot of vacuum hose and started routing it.


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I ended up running it into the back next to the fuel vent and ?Fuel Sender Cable?.

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Then used a small fuel filter as a breather with a bit more tube.  If water gets up to this point, then I have got bigger problems.

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Have not ran or fully tested this set up yet, still in the process of installing some electric fans and will finish zip tieing and mounting the breather tomorrow.

 

Let me know what you think!

Edited by Vegablade

It's a good idea. When I took a look at my diff I noticed the breather had so much gunk built up around it. Let me know how this turns out, I might want to do something similar. 

I used plastic barbed fittings slightly trimmed down to fit in all of my offroad diffs. They just pressed in. I did this on the car. That way I would not have to disassemble to drill.

Works fine . As long as the fittings are tight. lol

cheers

i ran my breather up under the rear seat bottom thru the grommet. same barb tho

I did the same trick a few months ago, but I ran my line up the middle of the trans tunnel to behind a front strut tower - this keeps any fumes outside of the cabin - I'm not convinced on the fuel filter trick.

 

One thing I'd do different is try to protect your line along the moustache bar - I did this on a previous diff, it ended up splitting due to a rock being flicked from the front end, diff oil went everywhere as the breather ended up being full of it as I didn't put a large enough bend in the top of it...

Cheers

Bennie

  • Author

I did the same trick a few months ago, but I ran my line up the middle of the trans tunnel to behind a front strut tower - this keeps any fumes outside of the cabin - I'm not convinced on the fuel filter trick.

 

One thing I'd do different is try to protect your line along the moustache bar - I did this on a previous diff, it ended up splitting due to a rock being flicked from the front end, diff oil went everywhere as the breather ended up being full of it as I didn't put a large enough bend in the top of it...

 

Cheers

 

Bennie

 

You used the same breather hole correct?  Shouldn't be any oil in the line as far as i can tell.  The port has a U shaped hole to keep oil out, should only be air.

 

As far a fumes go i'm not to worried about it.  I don't think the differential moves enough air through heat expansion to make it bad.  Plus my car already smells of gear oil.

 

I ran it yesterday and so far so good, didn't notice anything weird.  Will dump the diff oil soon and see how it looks.

Same breather hole.  I can't remember how long I had that last set up but there was a considerable amount of oil in the breather line.  

I'm much happier with how I've routed the hose up higher, any oil that ends up in the line will drain back.

Cheers


Bennie

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