Engine seal dripping on alternator
Thread Starter
Junior Member
Joined: Dec 2013
Posts: 50
Likes: 6
From: Bellevue WA
2016 E350
Engine seal dripping on alternator
At the dealer for a 78K Service A on my 2026 E350, I was told that there was an engine oil leak and that it should be fixed before it causes more damage. The cost was ~$2700. After choking and sputtering, I recalled that this same dealership had told me the same thing previously and that they had fixed it for ~$2K. They went and checked their records and then told me that this was to be covered under parts warranty. (Meaning at no cost.) What are the chances that both of these were scams and that there actually was no leak to be fixed? Further, has anyone had engine seal leak issues?
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Joined: Feb 2025
Posts: 10
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From: In Europe
W212 W221 and R172
That sounds really sketchy, especially since they first hit you with a $2,700 quote and only backed off when they realized their own records showed it was under warranty. Either they misdiagnosed it twice, or they were hoping you wouldn’t remember the previous repair and just pay up. Some dealerships definitely pull this kind of thing.
As for actual oil leaks on the E350, they’re not super common, but they do happen—usually from valve cover gaskets, oil pan gaskets, or rear main seals as the car ages. That said, if they supposedly fixed it already, you really shouldn’t be dealing with the same issue again so soon unless they messed something up the first time.
If you’re not convinced, I’d check for any visible oil drips under the car, inspect the engine bay for signs of leaks, or even get a second opinion from an independent Mercedes shop. If nothing shows up, then yeah, it sounds like they were just trying to squeeze some extra cash out of you. I hope you find a solution and that i've helped you
As for actual oil leaks on the E350, they’re not super common, but they do happen—usually from valve cover gaskets, oil pan gaskets, or rear main seals as the car ages. That said, if they supposedly fixed it already, you really shouldn’t be dealing with the same issue again so soon unless they messed something up the first time.
If you’re not convinced, I’d check for any visible oil drips under the car, inspect the engine bay for signs of leaks, or even get a second opinion from an independent Mercedes shop. If nothing shows up, then yeah, it sounds like they were just trying to squeeze some extra cash out of you. I hope you find a solution and that i've helped you
MBWorld Fanatic!
Joined: Feb 2003
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From: Charlotte, NC
Had: 1987 300TD, Had: 2004 C230 Sport Sedan, Have: 2014 E350 Sport, Have: 2019 S450
A leak requiring repair will leave enough residue to be easily noticeable. Don’t take their word for it. Open the hood and check for yourself.
Thread Starter
Junior Member
Joined: Dec 2013
Posts: 50
Likes: 6
From: Bellevue WA
2016 E350
Damn my typing. It is a 2016 E350. What they replaced were both upper timing covers which I do not believe can be seen without getting into it. This the second time for this replacement. Has anyone else had this issue?
MBWorld Fanatic!
Joined: Feb 2003
Posts: 1,414
Likes: 339
From: Charlotte, NC
Had: 1987 300TD, Had: 2004 C230 Sport Sedan, Have: 2014 E350 Sport, Have: 2019 S450
The timing covers are front of each V, at the top. Will be very evident if there is a leak.
https://youtu.be/OG4NfTjtlyE?si=UZGUpiBDaU72flo3
https://youtu.be/OG4NfTjtlyE?si=UZGUpiBDaU72flo3
Last edited by dmatre; Feb 21, 2025 at 08:32 PM.
MBWorld Fanatic!
Joined: May 2018
Posts: 6,600
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From: Jakarta-Indonesia
2014 - W212.065 - E400 ( M276.820, 3 liter Turbo) RWD not Hybrid
The M276 small window VVT timing cover is a bad job MB does, poor distribution of the sealant thus not 100% coverage.
The leak is so very slow ....
I too got the oil leak trace up to my alternator.
Its an easy DIY. No need to go to MB dealer.
https://mbworld.org/forums/e-class-w...lant-work.html
The leak is so very slow ....
I too got the oil leak trace up to my alternator.
Its an easy DIY. No need to go to MB dealer.
https://mbworld.org/forums/e-class-w...lant-work.html
MBWorld Fanatic!
Joined: May 2021
Posts: 2,524
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From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
We have 3 M276 NA engines @95K, 101K and 135K. Are timing covers sterile of any oil? Definitely not.
Worth spending $2000 to fix them and likely end up the same after a year, not a chance.
If there is any meaningful leak should be extremely obvious at the front if the engine. Unable to see the aluminum color, and the under trays dirty. Oil must be missing and I need to top off.
If in doubt, take a few photos of the front of the engine, including one looking down towards the under trays, post them and you will get several opinions here
Worth spending $2000 to fix them and likely end up the same after a year, not a chance.
If there is any meaningful leak should be extremely obvious at the front if the engine. Unable to see the aluminum color, and the under trays dirty. Oil must be missing and I need to top off.
If in doubt, take a few photos of the front of the engine, including one looking down towards the under trays, post them and you will get several opinions here
Last edited by JCM_MB; Feb 23, 2025 at 10:54 AM.
