1977 F250 4x4 Dana 60 rear end. The left side where the rubber brake hose fastens to the axle. You have the rubber brake hose that has the brass block where it fastens to the axle. There is a threaded piece that slides through the block and threads into the axel housing.

This threaded piece is obviously a breather vent for the axle as it has a nipple on it and there was a vent hose attached to it. I took mine out as it was full of crud.

I cleaned it out, yet I dont see how this piece actually vents. I cant get any air to pass through it. Even with 150psi. It is not a through hole in the piece. I dont understand how the air is supposed to pass through it.

Can anyone explain?

 

When I took mine out, there was a small hole. It had alot of crap and rust in it and did not see the hole until I sandblasted it.

 

I have never known the true reason for it, for mine wouldn't pass air either.
all I know after time on the Isuzoo forum, is to always leave it on, some of the guys on the forum there found out the hard way.

 

E7TZ4022A (replaced C2OZ4022A) .. Rear Axle Vent

Fits: 1962/2010 Passenger Cars, Trucks, Bronco's and Econolines.

Take a nail, probe around inside the vent. There is something plugging up its tiny hole....which ALL these vents have.

 

Thanks, guys. I will take it back out to try and clean it. At least I can get a new if I have to!!

 

Thanks, Buck... indeed it was plugged up with rust and a small drill bit twisted in by hand cleared out the hole. Then I blew out the vent hose with compressor to clean it out.

FYI...I suggest you all check this piece out if you have it. It should be VENTING. I had my axles out while doing my breaks only a couple of days ago, and put it back together. It was cold then. When I unscrewed this piece today to clean it out, a "wush" of air released when removed. That was just a difference of about 20* over two days (maybe more as sun was hitting axle) and it had that much pressure difference in it. Can only imagine when it gets hot under normal driving use and that vent is plugged!! CLEAN IT OUT!

 

That is one of the main reasons guys will chase oil leaks at the axle and pinion seals. Only to replace gasket after gasket after gasket just to find out the vent is plugged.

Josh

 

Bill can you verify that part number. I broke one of these and need a new one. My local Ford dealer says the number E7TZ4022A is no good. Not that Im doubting you, its just the guys here are never very helpful.

 

Jeffs Bronco Graveyard has these vents also..

 

I agree that a plugged vent will cause leaks. My 74 leaked at the weld on backside of the pumpkin and at pinion seal until I cleaned the vent

 

can you just run a regular aftermarket diff breather?

 

yes. anything that will let pressure out but that will not let dirt/water in.

 

Question for an old thread:
I just rebuilt my rear end and came across this vent tube and was confused at the time. The PO has clamped a rubber tube (3inches long) to the nipple and plugged it with a screw. I took that off, re-installed it, but now I'm seeing gear oil leaking (spraying) out from the nipple. Do I just let that happen (maybe I overfilled the rear end) or is there supposed to be a check valve or cap?

Also, there was split washer, not a copper washer, between the vent tube and the brass brake t-junction. Is that up to spec?

Thanks!

 

I was thinking there was a copper washer but can't be for sure. If it don't leak it should be ok.

My guess for the leaking out of the nipple vent tube is that the hose from the vent nipple is too short. It is supposed to be long enough to be able to tie up to the rear crossmember at least at a horizontal angle to prevent crud from entering the tube.

 

The washer is a standard split lock washer, not a copper one.
Like Buck said, the hose should be long enough to clip to the frame.
This is a Ford 9" but the principle is the same.