Boss Axle (No) Vent

[cholmes1]

Thank you @67GTA This is very helpful. I was leaning toward upgrading the fittings and given the feedback from Rick, it sounds like the majority of contact was coming from an oversized fixture mounted to the top of the diff cover. I am certain a solution can be made. Also, great insight on the custom hose with heat shielding, hopefully you can find your DYME invoice to simplify the process. It is good insurance given the harsh environment under there.

If you have an image of yours in its installed position, it would be great to have reference photos to see how you routed your hose

 

[67GTA]

Thank you @67GTA This is very helpful. I was leaning toward upgrading the fittings and given the feedback from Rick, it sounds like the majority of contact was coming from an oversized fixture mounted to the top of the diff cover. I am certain a solution can be made. Also, great insight on the custom hose with heat shielding, hopefully you can find your DYME invoice to simplify the process. It is good insurance given the harsh environment under there.

If you have an image of yours in its installed position, it would be great to have reference photos to see how you routed your hose

Here’s a screenshot of the configuration. The order number is on there too, so Brendan may be able to replicate from their records as well.




I won’t be around the car for a couple weeks, but will try and get a some reference pics in early July.

 

[67GTA]

Thank you @67GTA This is very helpful. I was leaning toward upgrading the fittings and given the feedback from Rick, it sounds like the majority of contact was coming from an oversized fixture mounted to the top of the diff cover. I am certain a solution can be made. Also, great insight on the custom hose with heat shielding, hopefully you can find your DYME invoice to simplify the process. It is good insurance given the harsh environment under there.

If you have an image of yours in its installed position, it would be great to have reference photos to see how you routed your hose

Another note on this - I’m using the port circled in red on the watts link cover in lieu of the one on top. Cortex v1 cover didn’t have the top vent port, which was the location on the stock Boss cover that was tough to get low enough to not interfere with the Bob’s can.

 

[cholmes1]

Yes. That is the tricky part on the Boss. I will need to find a very low profile AN fitting to go up top. Hopefully that, paired with your larger cutout idea, and it should give the space needed for full suspension articulation.

 

[galaxy]

Not crazy about the can in that Cortex pic. Drains downhill. This axle will vent. It'll work, you just gotta stay up on the checking/draining it. Here's my completely custom pieced together setup on my '12 GT. Now that I know this axle is holding pressure even with the stock vent, I'll probably add this same setup to the Boss. I like it.

 

[galaxy]

It's correct. In Boss cars the vent is on the top of the diff cover. It makes seepage a little less likely. The stock GT diff cover doesn't have this feature so on those cars it's on the axle.
View attachment 110758

My car doesn't have the two fill plugs (drain and I assume fill?) like that. Did you add those yourself?

 

[BackInBlack]

My car doesn't have the two fill plugs (drain and I assume fill?) like that. Did you add those yourself?

No, it's a FRPP Boss/GT500 diff cover. I just grabbed the photo from a product review.

https://lmr.com/item/M4033K/1986-11-Mustang-Gt500-Style-Finned-Aluminum-Rear-End-Cover

The bottom hole can be used for draining, but IMO it's a bad idea. If there's any metal bits or other crap in the fluid it'll mostly be at the bottom, and you can't get all of the fluid out that way. As for filling via the top hole, I'm pretty sure that'd overfill. Those holes are meant for a cooling system or an expansion reservoir.

 

[galaxy]

As for filling via the top hole, I'm pretty sure that'd overfill. Those holes are meant for a cooling system or an expansion reservoir.

It’s actually made for filling, but obviously not up to that level. You’re supposed to remove the factory fil plug on the front of the axle to monitor the quantity while you add fluid in that top hole. Ease of service, but it doesn’t change the required fill level. I have this one and that’s per the instructions.

 

[cholmes1]

A clean install @BackInBlack but once you make the decision to mount in the trunk the options are pretty limitless in terms of reservoir options and mounting locations. For those wanting to avoid the interior entirely, and ideally not drill new mounting holes, it is a different challenge.

 

[stevbd]

I use the old “turkey baster” bulb vent mounted on the top of an FRPP diff cover and that’s done the trick for me. But it appears that bulb vent is discontinued and Ford came out with this tube instead? This might be a good easy first step to try?

https://lmr.com/item/LRS-4022AA/ford-mustang-8-8-rear-axle-housing-vent-hose-kit-86-14?utm_source=google&utm_medium=cpc&gad_source=1&gad_campaignid=20122150534&gbraid=0AAAAAD62FUyPfCHeiA8sPSVCqudGhO5do&gclid=CjwKCAjwgO7RBhBKEiwAZNP85lpvU0sKhQphnZUp1BKbRImEftQIHSD6plVzJpYXC-KvqZmCp0X2kxoCBrUQAvD_BwE

Btw, I found the stock small metal vent to be pretty constrictive even when clean and new. Maybe I just got a bad one but it was hard to blow air through it.

 

[cholmes1]

Thank you, @stevbd I was unaware that Ford offered what amounts to an extension tube. Not certain how effective it would be on the track, but it would certainly allow a bit more leeway for expansion that the OE setup.

 

[stevbd]

I was unaware also. Seems Ford has taken a new swing at this since I last looked at this issue.

 

[Champale]

I just read the reviews in the link and people complain that it breaks when the suspension compresses on a lowered car.

 

[BackInBlack]

I use the old “turkey baster” bulb vent mounted on the top of an FRPP diff cover and that’s done the trick for me. But it appears that bulb vent is discontinued and Ford came out with this tube instead? This might be a good easy first step to try?

https://lmr.com/item/LRS-4022AA/ford-mustang-8-8-rear-axle-housing-vent-hose-kit-86-14?utm_source=google&utm_medium=cpc&gad_source=1&gad_campaignid=20122150534&gbraid=0AAAAAD62FUyPfCHeiA8sPSVCqudGhO5do&gclid=CjwKCAjwgO7RBhBKEiwAZNP85lpvU0sKhQphnZUp1BKbRImEftQIHSD6plVzJpYXC-KvqZmCp0X2kxoCBrUQAvD_BwE

Btw, I found the stock small metal vent to be pretty constrictive even when clean and new. Maybe I just got a bad one but it was hard to blow air through it.

I've seen that. That kit was the fix offered for TSB 14-0046 (leaky axle TSB)