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Got a new rear diff cover for my '08. I noticed the new one has a vent on the top, the old cover is solid. Do I need to cap an old vent somewhere else If I install this cover? Or leave this one out an cap it?
Rear diff. cover install
- Thread starter Mongopushn
- Start date
I replaced the cap with a catch bulb. Hard acceleration was spewing fluid so I replaced with the bulb - looks like a small turkey baster. Got it from Ford dealer.
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Your car might have a vent on the axle which is where they put them prior to using the aluminum cover. If you do have one, you can cap the cover. But you need at least one vent somewhere on the differential. Without one you could push oil out the seals. Frankly, it's better to use the higher location. The cover is also baffled for it.
I puked so much fluid through that stupid diff vent..
I ended up pulling the plug from the the left axle tube and shoving it in the diff cover. Installed the JLT catch can kit and its the bees knees. Works excellently
I ended up pulling the plug from the the left axle tube and shoving it in the diff cover. Installed the JLT catch can kit and its the bees knees. Works excellently
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Good info, thanks for the help.
Yes, my 2008 had the vent screwed into the right (passenger) side axle tube next to the assy. line barcode sticker.
Shown below right before the reinstall after my 2008 8.8 axle de-rust/restoration project......
In the picture above a fitting has replaced the original rattle vent and I installed a GT500KR style axle reservoir to keep my restored axle from getting any gear oil or vapor on the right tube. The gear oil/vapor ruins that barcode sticker, and that sticker is the correct "numbers matching" identifier for the 8.8 axle assy., a portion of the VIN is on the end of that sticker/label
R
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I installed the "New Ford Racing Reinforced
IRS Rear Diff Cover" on my 03 cobra. Kept loosing fluid out the vent tube (A LOT). It baked on the exhaust, got all over the rear of the car.... Finally I mounted a catch can. But then later I read that the new updated cover allows for more fluid capacity. I read that your supposed to add the required capacity, topping it off until it leaks out the hole is causing you to over fill. This might also be the case for any of you that are having the same problem? I never verified if this was true or measured the fluid. I just left the catch can on it.
IRS Rear Diff Cover" on my 03 cobra. Kept loosing fluid out the vent tube (A LOT). It baked on the exhaust, got all over the rear of the car.... Finally I mounted a catch can. But then later I read that the new updated cover allows for more fluid capacity. I read that your supposed to add the required capacity, topping it off until it leaks out the hole is causing you to over fill. This might also be the case for any of you that are having the same problem? I never verified if this was true or measured the fluid. I just left the catch can on it.
The only time I have heard of that happening is when an owner mistakenly uses the upper hole on the finned cover as the fill level instead of the original plug on the front of the diff. housing, drivers side if I remember correctly. The upper plug on that finned cover is way over fill for the 8.8. It is the return port where the line would connect for a GT500 that has the differential cooler set-up and well above the fluid fill level.
R
Thanks for the info, Its been a long time ago now but its due for a rebuild. Ill for sure look into that, I did fill from the cover :-/
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Can anyone help me with the size plug and thread pattern needed to cap with? I'm having trouble finding a match. Doesn't seem to be an m10 or an m12 size.
7/16 seems to be the closest fit but seems a tad smaller using my "boltsize-it" tool. I guess it could be m11 but seems like an odd size.
7/16 seems to be the closest fit but seems a tad smaller using my "boltsize-it" tool. I guess it could be m11 but seems like an odd size.
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Why use the axle vent instead of the diff. cover in the higher location? Besides the differentials, are the earlier axles different the the later models years like the Boss used?
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Try 1/8" NPT.
I was also spewing gear oil, it was brutal. My rear bumper would be coated in gear oil after every highway ride. I put the vent in the cover (I have the 13/14 cover) and left the one in the axle as well. I also put a Lube Locker gasket and ARP bolts in (they're longer which is necessary for the 13/14 cover). No more gear oil on my bumper and no smelly mess. The Lube Locker gasket is the beez kneez, very nice!
When I initially put the 13/14 cover on, I didn't even realize that there was a spot on top for the vent.
When I initially put the 13/14 cover on, I didn't even realize that there was a spot on top for the vent.
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Thanks, I found what I need after several forum searches. Also has an included o-ring. Only a few dollars from Summit Racing.
http://i1314.photobucket.com/albums/t566/dillehay1/20170606_152904_zps0r6gtqfg.jpg
http://i1314.photobucket.com/albums/t566/dillehay1/20170606_152904_zps0r6gtqfg.jpg
When you accelerate hard, the lube in the diff will transfer to the rear of the case. Especially when the oil is hot, it will force its way out of the vent. Capping the diff vent and placing an expansion system off the axle vent will let the thermal expansion of the oil take place, but not force it out to atmosphere.
Let me know if this works. I'm not too happy with my OEM plug.Thanks, I found what I need after several forum searches. Also has an included o-ring. Only a few dollars from Summit Racing.
Or swap to the FRPP G2 cover. No vent on it
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