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Different Differential Reservoir/Breather and Cooler Installations

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I wanted to bring all of these threads together in one central location and post what I'm doing with mine. I've had the Bob's canister installed for over two years and it has been hitting the top diff vent fittings and causing some noise and leaks. So I'm removing it and installing the Allstar breather in my trunk. You're fine with the Bob's but keep an eye on it and either connect it to the axle tube or use a shallower fitting on the top of the diff. This appears only to be an issue on cars that are lowered.

With the Allstar breather I'll run the vent hose up from the top of the diff and into the trunk. There is a spot on the passenger side to mount the breather. Then I'll run a second hose back down and out by the back of the car similar to how j3st3r did. I purchased the two bung breather for specifically so I don't have to vent in my trunk. I'll post photos and parts when I finish. In the meantime below are a few threads to browse. Thanks to everyone who has installed and shared their setups.

Early Allstar installation

https://trackmustangsonline.com/index.php?topic=1696.25

CIMG3123.jpg

Custom breather by j3st3r

https://trackmustangsonline.com/index.php?topic=5085.0

Breather and cooler by Black Boss

https://trackmustangsonline.com/index.php?topic=7429.0
 
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I don't remember the size but here's a photo of mine. @steveespo might know.

IMG_5175.JPG
 
The axle and cover breather hole threads are 7/16"-20, which I think is also -4AN. I had to source my fittings through jegs and summit racing, couldn't find anything locally.
 
Haha. Seems to be some disagreement on what fitting is used in the axle tubes.

Does anyone know what fitting they actually used in the axle tube?
 
I used a 7/16-20 (-4AN) fitting on the axle tube. 1/4" is probably close enough to work. Do a google search and you'll find some threads about this.
 
I ordered an allstar single bung breather/catch can. Im going to stop at the local offroad shop to pickup all the -AN fittings i need to complete the setup. I still have plenty of -10 Hose from my engine oil catch can install.
 

dmichaels

Papa Smurf
547
30
CT
installed my rear diff cooler setup today. Pieced it together and will run it this Monday/Tuesday at an event. A couple pics below, including the toggle switches I wired in to control from the drivers seat. One is for the diff cooler setup, the other is for my Accusump so I can pressurize oil right before I start the car and turn the system off after a session

Question for others - how much additional fluid did you add as a result of the tubing, pump, and radiator volume? I estimated about 3/4 of a quart (measured tubing, but did not test volume of radiator or pump...).

-img_4676_c57551174cc83a363a79d53943e26915b96fa50a.jpg

-img_4674_2bb63b66c285ea7a6c4aafc5c21840444309b288.jpg


-img_4673_5b953f5024c987b62ab01092fcc792e99067fded.jpg
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
When I did mine I couldn't find anything that fit the axle tube so I drilled out the stock breather, and machined a hose barb from some stainless steel bar stock and welded it to the stock gutted breather. Then I ran a 3/8" hose up to this tank that I made and I just let the fluid fill and then drain back as the car cools off so I don't lose any fluid.
Its been trouble free.

20664591_10155588540613535_6034990806788114934_n.jpg
 
I confirmed that a -4AN 45° fitting works perfectly in the top of the diff cover, i could not get it to thread into the axle tube though.

I need to buy a -4AN push lock hose and some different fittings this week. Then i will post a parts list of everything i used so people of the future can easily get what works for them.

The biggest problem i have found is that nobody has posted part numbers and specific info for others.
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
I confirmed that a -4AN 45° fitting works perfectly in the top of the diff cover, i could not get it to thread into the axle tube though.

I need to buy a -4AN push lock hose and some different fittings this week. Then i will post a parts list of everything i used so people of the future can easily get what works for them.

The biggest problem i have found is that nobody has posted part numbers and specific info for others.
That's why I had to make mine from scratch...who knew?
 
Ok, here are pics of everything i am using. All you need to do is aquire a can with a 3/8NPT fitting on it.

I chose the single bung Allstar breather can. I am using -6AN pushlock hose.

The axle tube, and top of the finned diff cover both use the -4AN fitting, tne 3/8 NPT fitting goes into the can.

I am plugging the side bung on tje Allstar can with a 3/8 NPT fragola plug. I will plumb my hose to the bottom of the can so the can (if it ever accumulates oil) will self drain back into the rear end. And if it does fill the entire can, and blow through the top...i guess the trunk will catch it and i probably have other issues that are more important.

Picture of everything needed:
https://flic.kr/p/YKUZrV

10' of -6AN Fragola pushlock hose part #:
https://flic.kr/p/XFcvvb

Closeup of all the Fragola fittings:
https://flic.kr/p/YHnEi9

Fragola fittings Part numbers:
https://flic.kr/p/YKUYPH

With the purchase of the Allstar can, and all the Fragola parts i am right at $150 total for this project. I ordered the Allstar can on Amazon which was fairly cheap, and had free shipping. The Fragola stuff was sourced locally and i paid more for it to support my favorite local shop, plus i paid tax.

I know for a fact you can save a few bucks by ordering the Fragola stuff off summitracing.com

Either way its cheaper than buying the Boss 302s kit (which is the exact same parts) that sells for $170-$200 at Kohr.
 

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