Question about front diff breather tube

So,

About a month ago I started noticing my front diff leaking. I was concerned and thought something was actually wrong with the housing/seals etc and decided to just park the truck until I had time to further diagnose.

Well, last week I looked around the housing and also searched here on the forums for some possible causes and I didn't find any actual areas on the diff where it appeared to be leaking, so where was this gear oil coming from?

Turns out, it was "vomiting" right at the connection point where the front diff output nozzle thingie "marries" together with the main tube that goes to the engine bay. There is about a 3 inch long, thick piece of tube that does the "marrying" and right there is where it was barfing.

So... What I did to resolve this issue:

1) Opened the diff fill cap and noticed a bit actually come out (as if it were over-filled? )
2) I went to autozone and got some tiny "hose clamps" and actually put hose clamps on each end of the 3" hose parts (stock has none, it just "fits over the nozzel").
3) I removed the "cap" at the top of the breather hose in the engine bay. I didn't want to leave the tube (and thus the diff) "open to the elements" so I taped most of it off with gorilla but left a tiny pin hole for air to escape. This is where the question is. What is the correct working function of the breather cap? The reason I ask is because mine didn't allow any "air" or movement. It was effectively sealed air tight, hence the "vomiting" at the weak point.

Please advise: Should these "caps" be breathable or sealed like it was?

Any and all help will be grateful, and yes I did search. I can post pics if necessary, but if you know what I'm referring to, then you already have an idea.

Thanks!

 

did you get this figured out, I know this is an old thread! i did the rear mod, but want to do a front diff mod if anyone has done it