CX-5 AWD Rear Diff Breather

Yeap, this one-way check valve mounted on top of the rear differential casing is the "exhaust". The "intake" is at the side and a bit lower with a very long vent hose routed to upper rear bumper area.

Well...huh. I have no clue how mine sucked up water. Maybe the hot diff plus cold water generated some pressure diff somehow and who the hell knows?
 
Wow that is a really simple design. I guess its possible the rubber washer could distort in a way that it doesn't seal properly. Or maybe if driven under dusty conditions dirt and debris can get stuck and compromise the seal. Can you tell me the diameter and thread pitch? There is a McMaster Carr warehouse not too far from me, I might be able to find something for you AWD guys.

Ok... bear in mind this is with my $15 HF caliper :) and all measurement are approximates.


Diameter: 7.85mm/.3 inch

Thread grove-to-groove: 1.8mm/0.07 inch

Thread-to-thread: 1.23mm/0.049 inch

Stock length of entire breather: 35mm/1.415 inch

Threaded piece of breather: 13mm/ .51 inch
 
Ok... bear in mind this is with my $15 HF caliper :) and all measurement are approximates.


Diameter: 7.85mm/.3 inch

Thread grove-to-groove: 1.8mm/0.07 inch

Thread-to-thread: 1.23mm/0.049 inch

Stock length of entire breather: 35mm/1.415 inch

Threaded piece of breather: 13mm/ .51 inch

Oh, you dont have a thread gauge?
 
Actually no.. haven't had a need for one really.. let me see if I can pick up a cheap one :)
 
well you dont need to buy one, if you just happen to stop by lowes or home depot, and myabe even autozone, they might just measure it for you
 
Looks like diameter is 8mm according to gauge I bought and thread pitch is 1.25mm
 
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Looks like diameter is 8mm according to gauge I bought and thread pitch is 1.25mm

Ok its a metric thread. That will limit choices in getting a barbed connection for a hose or tube for the breather if you guys want to do the breather mod. They usually come in NPT or BSPT threads, like this:

1_zpsb8ycusot.jpg


Ideal size would be a 1/4'' to 5/16'' or 8mm barbed to M8x1.25 fitting, but google doesnt show anything. I thought I found a nice aluminum Earl's fitting from Summit but I cant seem to find it anymore. So this leaves you AWD guys with either:

A) Buying the same breather part, cutting off the hat on the one that goes to the diff, stick a hose over it and extend it up, maybe follow up the gas fill tube, and then sticking the other intact breather in the tube, fasten everything and zip tie to secure.

Judging by your first pics, I dont know if theres enough surface area over the breather to secure the hose. it might still leak.

B) Someone can try to fabricate a fitting and do steps above

C) Find an adapter that converts metric to NPT/BSPT, install a common fitting, do steps above

D) Drill and tap a thread to fit a more common fitting, do steps from A)

Or

E) There is a breather for the automatic transmission that also has a hose attached to it that goes into the tranny. The diagram shows it extending all the way up. Perhaps this breather might have the same threads and could be used with the hose for the breather mod.
 
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Not that I am aware of... I'll probably come back to this.. Currently working on the same thing on a GX 460
 
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