Rear Axle leak?
Thread Starter
Intermediate
Joined: Oct 2009
Posts: 30
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Rear Axle leak?
I have find oil around the vent tube and on the left side of my rear axle on my C5.
When I open the fillplugg I hear that air is leaking into the axle, and when I drive the car and leave it over the night and open the fillplugg again there is more vacuum inside.
Is that normal?
The fluid level is OK about 3mm from then bottom of the hole
I have cleaned the outside of the axle and it does´t seams to leak any more, but I want to know if this is normal or if I have to fix something.
/Fredrick
When I open the fillplugg I hear that air is leaking into the axle, and when I drive the car and leave it over the night and open the fillplugg again there is more vacuum inside.
Is that normal?
The fluid level is OK about 3mm from then bottom of the hole
I have cleaned the outside of the axle and it does´t seams to leak any more, but I want to know if this is normal or if I have to fix something.
/Fredrick
Last edited by LNZ; Oct 22, 2009 at 05:00 AM.
Tech Contributor
Joined: May 2008
Posts: 2,843
Likes: 16
From: Howell Michigan
St. Jude Donor '09-'10-'11
I have find oil around the vent tube and on the left side of my rear axle on my C5.
When I open the fillplugg I hear that air is leaking into the axle, and when I drive the car and leave it over the night and open the fillplugg again there is more vacuum inside.
Is that normal?
The fluid level is OK about 3mm from then bottom of the hole
I have cleaned the outside of the axle and it does´t seams to leak any more, but I want to know if this is normal or if I have to fix something.
/Fredrick
When I open the fillplugg I hear that air is leaking into the axle, and when I drive the car and leave it over the night and open the fillplugg again there is more vacuum inside.
Is that normal?
The fluid level is OK about 3mm from then bottom of the hole
I have cleaned the outside of the axle and it does´t seams to leak any more, but I want to know if this is normal or if I have to fix something.
/Fredrick
The left output shaft seal at the left side covers are known to go bad. The seal design was updated for the replacement seal. You may need to change it once the leak gets worse. Also the left side cover o'ring seal can leak. I would suggest replacing both once the leak gets bad enough to start leaving droplets on the floor of your garage.
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From: Somers, CT and Clermont, FL
St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16
Melting Slicks
Joined: Jan 2004
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From: Jensen Beach FL
Yes, that is normal. The vent is designed to open at about 1/2 psi of pressure and will hold up to 7.25 psi differential (vacuum).
The left output shaft seal at the left side covers are known to go bad. The seal design was updated for the replacement seal. You may need to change it once the leak gets worse. Also the left side cover o'ring seal can leak. I would suggest replacing both once the leak gets bad enough to start leaving droplets on the floor of your garage.
The left output shaft seal at the left side covers are known to go bad. The seal design was updated for the replacement seal. You may need to change it once the leak gets worse. Also the left side cover o'ring seal can leak. I would suggest replacing both once the leak gets bad enough to start leaving droplets on the floor of your garage.
Thread Starter
Intermediate
Joined: Oct 2009
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Thanks!
I don´t think I have any leak from the output shaft seal or side covers, because then it won´t be available to hold the vacuum.
I think the oil has been blown out from the vent pipe while driving, I have never seen any oil on the garage floor.
Well... it´s clean now and I have still don´t seen any more oil so I hope there is no problem to fix for me.
The car is an 2001 C5 with 18019 miles
I don´t think I have any leak from the output shaft seal or side covers, because then it won´t be available to hold the vacuum.
I think the oil has been blown out from the vent pipe while driving, I have never seen any oil on the garage floor.
Well... it´s clean now and I have still don´t seen any more oil so I hope there is no problem to fix for me.
The car is an 2001 C5 with 18019 miles
Tech Contributor
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From: Howell Michigan
St. Jude Donor '09-'10-'11
I've had my seal replaced 2 times on my 04. Both under warranty (new and extended warranty). Now that I am out of warranty the leak has returned and is only a couple drops on my garage floor. I am going to leave it alone till it gets a lot worse since it seems the issue is doomed to repeat itself.
Le Mans Master
Joined: Sep 2003
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From: Longview Texas
I have a 2004 Z06 and I have never seen any leaks around the axle seals, but last weekend I did some extended highway speed driving, and there was a couple of drops on the floor when I got back.
I could trace the fluid all the way to the top of the housing, so I am fairly sure it was coming from the vent. I think that the leak out the vent may depend on what temperature the rear end fluid gets up to.
I cleaned the area around the vent and the case, and have not seen any more signs of a leak.
I could trace the fluid all the way to the top of the housing, so I am fairly sure it was coming from the vent. I think that the leak out the vent may depend on what temperature the rear end fluid gets up to.
I cleaned the area around the vent and the case, and have not seen any more signs of a leak.
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I've already done the side cover repair myself as well as the axle bearing seals. I have had no issues until last week. It appears there is a bit of fluid that came down from the vent after a high speed highway run. I know the vent can weep a bit but you really need to keep an eye on the fluid level and the left side cover of the rear end and the axle bearing seal on the left (driver's side).
A buddy of mine who is a very competent GM/Corvette mechanic looked at it and is convinced it is from the vent. He also said almost everyone he has looked at will weep a small amount from the vent occasionally.
A buddy of mine who is a very competent GM/Corvette mechanic looked at it and is convinced it is from the vent. He also said almost everyone he has looked at will weep a small amount from the vent occasionally.
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From: Jensen Beach FL
Tech Contributor
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From: Howell Michigan
St. Jude Donor '09-'10-'11
Melting Slicks
Joined: Jan 2004
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From: Jensen Beach FL
It's what I use in my DTE real. In fact DTE will void the warranty if you don't. They say it's the best out there. I also add the Red Line additive even though the kind I bought had it in. DTE recommends additional limited slip additive. Don't know what is recommended with OEM gears.
