LS Rear differential vent....
Bullitt Member
Joined: July 1, 2011
Posts: 279
Likes: 0
From: SD
top of your differential cover has a functional vent.
I've got a "turkey baster" on the axle.
Gary runs a turkey baster on axle and top of differential cover. But he runs flat out so I guess he needs it.
I've got a "turkey baster" on the axle.
Gary runs a turkey baster on axle and top of differential cover. But he runs flat out so I guess he needs it.
Tasca Super Boss 429 Member
Joined: December 18, 2010
Posts: 3,708
Likes: 0
From: NorCal
V6 Member
Joined: February 8, 2011
Posts: 65
Likes: 0
From: Colorado
Shelby GT350 Member
Joined: November 20, 2010
Posts: 2,382
Likes: 1
From: Sioux Falls, SD
It was a TSB Ford issued due to diff fluid venting under extreme (read track) conditions. It provides additional expansion capacity along with a functional vent if the fluid expands beyond the volume provided by the "turkey baster". One issue with the axle location is clearance to the exhasut. As you can see from my pics, I melted the top of the vent on the axle turkey baster. I subsequently ordered an additional one to replace the factory vent on top of the diff cover, thus double basted 
I ran the two basters at the Mustang Roundup at MPH and had no venting issues. I haven't run them at BIR yet, where the mile long straight really heats up the diff, so I can't say with 100% certainty the problem is solved. That said, it was venting even at MPH with just one baster previously, so I think this will be adequate. On my GT500 I used a piece of tubing attached to a breather filter on the axle which allowed the fluid to go into the filter and drain back down into the axle. A friend of mine with a 5.0 rigged a catch can to some hose and ran it into his trunk. He has a breather filter on top of that in case it went beyond the filter, but it never got as high as the can during that same weekend at MPH.
I ran the two basters at the Mustang Roundup at MPH and had no venting issues. I haven't run them at BIR yet, where the mile long straight really heats up the diff, so I can't say with 100% certainty the problem is solved. That said, it was venting even at MPH with just one baster previously, so I think this will be adequate. On my GT500 I used a piece of tubing attached to a breather filter on the axle which allowed the fluid to go into the filter and drain back down into the axle. A friend of mine with a 5.0 rigged a catch can to some hose and ran it into his trunk. He has a breather filter on top of that in case it went beyond the filter, but it never got as high as the can during that same weekend at MPH.
Last edited by cloud9; Oct 6, 2011 at 07:09 AM.
Cobra Member
Joined: August 5, 2008
Posts: 1,369
Likes: 0
From: Arvada, CO
Old Shelby KR solution, not made anymore, but to give you an idea of what can be done:
http://www.shelbystore.com/ProductDe...e=8R3V-4022-KR
http://www.shelbystore.com/ProductDe...e=8R3V-4022-KR
Bullitt Member
Joined: October 21, 2004
Posts: 424
Likes: 0
From: Warsaw, IN
It was a TSB Ford issued due to diff fluid venting under extreme (read track) conditions. It provides additional expansion capacity along with a functional vent if the fluid expands beyond the volume provided by the "turkey baster". One issue with the axle location is clearance to the exhasut. As you can see from my pics, I melted the top of the vent on the axle turkey baster. I subsequently ordered an additional one to replace the factory vent on top of the diff cover, thus double basted I ran the two basters at the Mustang Roundup at MPH and had no venting issues. I haven't run them at BIR yet, where the mile long straight really heats up the diff, so I can't say with 100% certainty the problem is solved. That said, it was venting even at MPH with just one baster previously, so I think this will be adequate. On my GT500 I used a piece of tubing attached to a breather filter on the axle which allowed the fluid to go into the filter and drain back down into the axle. A friend of mine with a 5.0 rigged a catch can to some hose and ran it into his trunk. He has a breather filter on top of that in case it went beyond the filter, but it never got as high as the can during that same weekend at MPH.
I ran the two basters at the Mustang Roundup at MPH and had no venting issues. I haven't run them at BIR yet, where the mile long straight really heats up the diff, so I can't say with 100% certainty the problem is solved. That said, it was venting even at MPH with just one baster previously, so I think this will be adequate. On my GT500 I used a piece of tubing attached to a breather filter on the axle which allowed the fluid to go into the filter and drain back down into the axle. A friend of mine with a 5.0 rigged a catch can to some hose and ran it into his trunk. He has a breather filter on top of that in case it went beyond the filter, but it never got as high as the can during that same weekend at MPH.
V6 Member
Joined: May 22, 2011
Posts: 76
Likes: 1
From: Littleton, CO
TURKEY BASTER THEORY OF OPERATION
As the car is driven, the axle heats above ambient temps from internal friction and the air inside the axle expands. Ford installs breather cap or vent on top of the Boss’ differential cover. The vent allows the axle to breathe and not pressurize the wheel bearing oil seals or the front differential oil seals.
The ring gear is partially submerged in gear oil and as it rotates it slings gear oil inside the differential housing. The faster the ring gear spins, the more gear oil it slings and the more the oil is atomized. As the axle breathes, some of the small atomized oil droplets can pass through the vent. The turkey baster provides a location where the flow speed of vented oil droplets will slow down and coalesce on the walls of the baster bulb. After they coalesce into larger droplets, they drain back into the axle.
If the speed of the vented air is higher, oil droplets are carried out the axle vent = oily, drippy rear axle, suspension and back bumper cover.
I ran a single turkey baster on top of the differential cover at MSR-Houston two weekends ago and it puked oil big time. In the pits it caused a 6 inch oil puddle under the car between runs. MSR-Houston is a 17 turn 2.38 mile course www.msrhouston.com . Ambient temperature was 94-96 degrees. Top speed on the front and back straights was 120-130 mph.
Perhaps a second turkey baster installed on the axle tube could keep the air vent speed below oil puking velocity. If that fails it may be time to punt the turkey baster and install a 3 foot long piece of rubber hose at the top of the differential, install the original vent at the other end and route and secure the vented end to the car body.
As the car is driven, the axle heats above ambient temps from internal friction and the air inside the axle expands. Ford installs breather cap or vent on top of the Boss’ differential cover. The vent allows the axle to breathe and not pressurize the wheel bearing oil seals or the front differential oil seals.
The ring gear is partially submerged in gear oil and as it rotates it slings gear oil inside the differential housing. The faster the ring gear spins, the more gear oil it slings and the more the oil is atomized. As the axle breathes, some of the small atomized oil droplets can pass through the vent. The turkey baster provides a location where the flow speed of vented oil droplets will slow down and coalesce on the walls of the baster bulb. After they coalesce into larger droplets, they drain back into the axle.
If the speed of the vented air is higher, oil droplets are carried out the axle vent = oily, drippy rear axle, suspension and back bumper cover.
I ran a single turkey baster on top of the differential cover at MSR-Houston two weekends ago and it puked oil big time. In the pits it caused a 6 inch oil puddle under the car between runs. MSR-Houston is a 17 turn 2.38 mile course www.msrhouston.com . Ambient temperature was 94-96 degrees. Top speed on the front and back straights was 120-130 mph.
Perhaps a second turkey baster installed on the axle tube could keep the air vent speed below oil puking velocity. If that fails it may be time to punt the turkey baster and install a 3 foot long piece of rubber hose at the top of the differential, install the original vent at the other end and route and secure the vented end to the car body.
Last edited by 2012-LS134; Oct 6, 2011 at 01:45 PM.
Bullitt Member
Joined: July 15, 2011
Posts: 441
Likes: 0
TURKEY BASTER THEORY OF OPERATION
As the car is driven, the axle heats above ambient temps from internal friction and the air inside the axle expands. Ford installs breather cap or vent on top of the Boss’ differential cover. The vent allows the axle to breathe and not pressurize the wheel bearing oil seals or the front differential oil seals.
The ring gear is partially submerged in gear oil and as it rotates it slings gear oil inside the differential housing. The faster the ring gear spins, the more gear oil it slings and the more the oil is atomized. As the axle breathes, some of the small atomized oil droplets can pass through the vent. The turkey baster provides a location where the flow speed of vented oil droplets will slow down and coalesce on the walls of the baster bulb. After they coalesce into larger droplets, they drain back into the axle.
If the speed of the vented air is higher, oil droplets are carried out the axle vent = oily, drippy rear axle, suspension and back bumper cover.
I ran a single turkey baster on top of the differential cover at MSR-Houston two weekends ago and it puked oil big time. In the pits it caused a 6 inch oil puddle under the car between runs. MSR-Houston is a 17 turn 2.38 mile course www.msrhouston.com . Ambient temperature was 94-96 degrees. Top speed on the front and back straights was 120-130 mph.
Perhaps a second turkey baster installed on the axle tube could keep the air vent speed below oil puking velocity. If that fails it may be time to punt the turkey baster and install a 3 foot long piece of rubber hose at the top of the differential, install the original vent at the other end and route and secure the vented end to the car body.
As the car is driven, the axle heats above ambient temps from internal friction and the air inside the axle expands. Ford installs breather cap or vent on top of the Boss’ differential cover. The vent allows the axle to breathe and not pressurize the wheel bearing oil seals or the front differential oil seals.
The ring gear is partially submerged in gear oil and as it rotates it slings gear oil inside the differential housing. The faster the ring gear spins, the more gear oil it slings and the more the oil is atomized. As the axle breathes, some of the small atomized oil droplets can pass through the vent. The turkey baster provides a location where the flow speed of vented oil droplets will slow down and coalesce on the walls of the baster bulb. After they coalesce into larger droplets, they drain back into the axle.
If the speed of the vented air is higher, oil droplets are carried out the axle vent = oily, drippy rear axle, suspension and back bumper cover.
I ran a single turkey baster on top of the differential cover at MSR-Houston two weekends ago and it puked oil big time. In the pits it caused a 6 inch oil puddle under the car between runs. MSR-Houston is a 17 turn 2.38 mile course www.msrhouston.com . Ambient temperature was 94-96 degrees. Top speed on the front and back straights was 120-130 mph.
Perhaps a second turkey baster installed on the axle tube could keep the air vent speed below oil puking velocity. If that fails it may be time to punt the turkey baster and install a 3 foot long piece of rubber hose at the top of the differential, install the original vent at the other end and route and secure the vented end to the car body.
Anyone else having problems with just 1 turkey baster?
Shelby GT350 Member
Joined: November 20, 2010
Posts: 2,382
Likes: 1
From: Sioux Falls, SD
When I just had the one installed on the axle, and the factory vent on top of the diff, I still have a fair amount of fluid venting out. That could be because the path of least resistance was that vent, but I'm not sure. I never ran it with just the single turkey baster on the diff cover and leaving the bolt in the axle. I installed it there initially because I wasn't sure there was adequate clearance on top of the diff cover with the suspension fully compressed. After 2006Mach1 pointed it out, I realized there is more than enough clearance up there for it.
Bullitt Member
Joined: August 28, 2006
Posts: 430
Likes: 0
Old Shelby KR solution, not made anymore, but to give you an idea of what can be done:
http://www.shelbystore.com/ProductDe...e=8R3V-4022-KR
http://www.shelbystore.com/ProductDe...e=8R3V-4022-KR
I'm a little susprised no one has started making a kit for our cars.........
Bullitt Member
Joined: January 16, 2011
Posts: 200
Likes: 1
Old Shelby KR solution, not made anymore, but to give you an idea of what can be done:
http://www.shelbystore.com/ProductDe...e=8R3V-4022-KR
http://www.shelbystore.com/ProductDe...e=8R3V-4022-KR
http://www.svtperformance.com/forums...reservoir.html
You can purchase them from http://shop.bobsautosports.com/Musta...-reservoir.htm
Cobra Member
Joined: August 5, 2008
Posts: 1,369
Likes: 0
From: Arvada, CO
It isn't that they are no longer made but rather that Shelby has decided to sell what stock they have to KR owners only. They used to sell them to anyone...
Surprise! Someone DOES make a kit.
You can purchase them from http://shop.bobsautosports.com/Musta...-reservoir.htm
Surprise! Someone DOES make a kit.
You can purchase them from http://shop.bobsautosports.com/Musta...-reservoir.htm
Oh! I think I got one of the last ones a few years ago before that happened then.
This other piece looks much nicer than the Shelby, and about the same price.
Anyone with welding skills can fab one up for much less, I'd imagine.
I have the KR bottle but have not installed. Our race car and my previous '06 would puke quite a bit. Had the KR can on my 06, and on the race car, just a line going to a Dasani bottle zip-tied to the back of the fuel tank.
Haven't seen any puking on the BOSS yet w/ the higher vent location. I am pleased.
Haven't seen any puking on the BOSS yet w/ the higher vent location. I am pleased.
Tasca Super Boss 429 Member
Joined: December 18, 2010
Posts: 3,708
Likes: 0
From: NorCal