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Oil leak causing smoke

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Old Oct 1, 2019 | 12:28 AM
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Default Oil leak causing smoke

I have a 2003 base with 142k miles 6 speed and its developed a pretty bad leak and creates a big mess on the underside of the car. After driving around the oil gets all on the exhaust and cats. As a result, the car smoke quite a bit at stops. I’ve checked the oil pressure sensor, cam shaft sensor, and valve covers, it’s none of them. it drips from the back of the pan on both sides evenly. This leads me to believe it’s either one of the pan gaskets or the rear main but i also have some doubt of it being the rear main due to there being oil all the way up to the front of the pan. I’d like other people’s help with this problem on where it could be coming from and ways to go about this.


how the underside of the passenger side looked before any cleaning

how it looked after driving, oil clearly all over both sides of exhaust

after cleaning the underside and driving the car around the neighborhood to let it warm up

that black plate removed, looks dry behind there. I feel like it should be wet if it was the rear main. correct me if im wrong.

Last edited by wgm1993; Oct 1, 2019 at 12:29 AM.
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Old Oct 1, 2019 | 09:58 AM
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My '99 M6 Vert with 151K miles smokes from oil on the exhaust too. Entire oil pan is wet. I'll be changing my front seal and balancer next week. I'll let you know how that works for me.
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Old Oct 1, 2019 | 06:55 PM
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You probably have a bad front main and the seal at the bottom of the timing cover and rear main cover are leaking. The timing and rear main covers get a dab of RTV sealant in the corners that has probably dried up from the heat cycles the car has been through.
I would start with a thorough cleaning of the motor then get under it after every drive to see where it is starting to have oil appear.

From your pictures, it has been leaking for a while.

Gary
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Old Oct 1, 2019 | 07:26 PM
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Originally Posted by SilverC54me
You probably have a bad front main and the seal at the bottom of the timing cover and rear main cover are leaking. The timing and rear main covers get a dab of RTV sealant in the corners that has probably dried up from the heat cycles the car has been through.
I would start with a thorough cleaning of the motor then get under it after every drive to see where it is starting to have oil appear.

From your pictures, it has been leaking for a while.

Gary

the oil seeps from here after a clean up
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Old Oct 2, 2019 | 02:01 AM
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Highly likely the rear main has failed.

Gary
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Old Oct 2, 2019 | 03:33 PM
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Rear main, upper pan gasket, been there. Just do them both, you have to tear it all apart anyway. Not a bad one to have a pro do, you have to drop the front cradle for the pan gasket and drop the driveline for the rear main.
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Old Apr 16, 2020 | 02:39 AM
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Originally Posted by Danlb
My '99 M6 Vert with 151K miles smokes from oil on the exhaust too. Entire oil pan is wet. I'll be changing my front seal and balancer next week. I'll let you know how that works for me.
how did it go?
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Old Oct 10, 2021 | 01:52 AM
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Replaced rear engine cover entirely and no more leak
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