M-Class (W166) Produced 2012-2015

Oil leak evident under transfer case

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Feb 15, 2018 | 01:46 PM
  #1  
GregW / Oregon's Avatar
Thread Starter
MBWorld Fanatic!
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Jul 2003
Posts: 6,770
Likes: 1,264
From: Lake Oswego, OR
2020 GLE 450; 2023 BMW M2 Coupe
Oil leak evident under transfer case - 2012 ML350

I noticed oil drips on the garage floor and checked and found drips hanging under the transfer case. It's at the dealer for diagnosis now, but anyone else had this? '12 ML350, 53k mi.

Last edited by GregW / Oregon; Feb 20, 2018 at 06:37 PM.
Reply
Old Feb 15, 2018 | 02:31 PM
  #2  
pcy's Avatar
pcy
MBWorld Fanatic!
 
Joined: Mar 2004
Posts: 1,175
Likes: 24
From: Boston, MA
'14 ML350, '13 C220 CDI, '07 C280, '98 ML320
Was there any work done on the vehicle recently? Any repair work done on transfer case? or the connected drive-shafts?
Let us know what the dealer's diagnosis is...
Reply
Old Feb 16, 2018 | 08:45 PM
  #3  
GregW / Oregon's Avatar
Thread Starter
MBWorld Fanatic!
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Jul 2003
Posts: 6,770
Likes: 1,264
From: Lake Oswego, OR
2020 GLE 450; 2023 BMW M2 Coupe
'12 ML350 transfer case leak

Originally Posted by pcy
Was there any work done on the vehicle recently? Any repair work done on transfer case? or the connected drive-shafts?
Let us know what the dealer's diagnosis is...
No work had been done before this. I am told the "inner seal" needs to be replace which requires removing the transfer case at a cost of $1,439! Seems like a very odd issue to happen at this low mileage. I am contacting the service manager to see if any "goodwill" assistance is available.
Reply
Old Feb 19, 2018 | 09:31 PM
  #4  
Packrat555's Avatar
Junior Member
 
Joined: Jan 2018
Posts: 46
Likes: 5
From: Arlington TX
2013 GL450
"inner seal" of what? sounds like bs to me. If they have to pull the transfer case and crack it open to replace an inner seal seems like it would be way more expensive.

It looks like oil drips are at the end of the bolts. It also looks like the bolts have be wrenched on since new at the factory as there is evidently some visual stripping of the heads. It also looks like there may be a seal under the bolts. If it were my car I would try to find a way seal the bolts with rtv or o-ring type seal. I would be suspicious that is all the dealer will do when charging you $1400
Reply
Old Feb 19, 2018 | 10:55 PM
  #5  
GregW / Oregon's Avatar
Thread Starter
MBWorld Fanatic!
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Jul 2003
Posts: 6,770
Likes: 1,264
From: Lake Oswego, OR
2020 GLE 450; 2023 BMW M2 Coupe
Oil leak evident under transfer case

I am definitely suspicious. I have asked the service manager for a better explanation. No work has been done on the car except for routine maintenance, AFAIK.
Reply
Old Feb 20, 2018 | 06:49 PM
  #6  
GregW / Oregon's Avatar
Thread Starter
MBWorld Fanatic!
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Jul 2003
Posts: 6,770
Likes: 1,264
From: Lake Oswego, OR
2020 GLE 450; 2023 BMW M2 Coupe
Oil leak at transfer case - 2012 ML350

Originally Posted by Packrat555
"inner seal" of what? sounds like bs to me. If they have to pull the transfer case and crack it open to replace an inner seal seems like it would be way more expensive.

It looks like oil drips are at the end of the bolts. It also looks like the bolts have be wrenched on since new at the factory as there is evidently some visual stripping of the heads. It also looks like there may be a seal under the bolts. If it were my car I would try to find a way seal the bolts with rtv or o-ring type seal. I would be suspicious that is all the dealer will do when charging you $1400
Further update: The leak is said to be at the main shaft seal. This does require removing the transfer case. The Assistant Service Manager at the dealership (Mercedes-Benz of Wilsonville) has offered a 50% Goodwill assistance. That's the best I could hope for.

Last edited by GregW / Oregon; Feb 21, 2018 at 09:24 AM.
Reply
Old Feb 22, 2018 | 12:56 PM
  #7  
pcy's Avatar
pcy
MBWorld Fanatic!
 
Joined: Mar 2004
Posts: 1,175
Likes: 24
From: Boston, MA
'14 ML350, '13 C220 CDI, '07 C280, '98 ML320
Originally Posted by GregW / Oregon
Further update: The leak is said to be at the main shaft seal. This does require removing the transfer case. The Assistant Service Manager at the dealership (Mercedes-Benz of Wilsonville) has offered a 50% Goodwill assistance. That's the best I could hope for.
Leak from main shaft seal may be migrating to the lower points on the transfer case. That's plausible. After the work is done, keep an eye on that area to make sure the leak doesn't come back.

On my ML350, a leak from the shaft seal was spread on the bell housing and the surrounding area. I took photos and showed them and they replaced the drive shaft (not just the seal) under warranty few months ago.
Reply
Old Feb 22, 2018 | 01:19 PM
  #8  
GregW / Oregon's Avatar
Thread Starter
MBWorld Fanatic!
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Jul 2003
Posts: 6,770
Likes: 1,264
From: Lake Oswego, OR
2020 GLE 450; 2023 BMW M2 Coupe
Leaking transfer case seal

Originally Posted by pcy
Leak from main shaft seal may be migrating to the lower points on the transfer case. That's plausible. After the work is done, keep an eye on that area to make sure the leak doesn't come back.

On my ML350, a leak from the shaft seal was spread on the bell housing and the surrounding area. I took photos and showed them and they replaced the drive shaft (not just the seal) under warranty few months ago.
How many miles on your car when it started leaking? Any idea if there is an internal technical bulletin out? I found a document, LP128-10-P-051935 related to the GLK350 that addresses leaks at the transmission/transfer case joint. I also found this post: http://www.peachparts.com/shopforum/...case-leak.html & this https://www.carcomplaints.com/Merced...fer_case.shtml.

Last edited by GregW / Oregon; Feb 22, 2018 at 01:34 PM.
Reply
MB World Stories

The Best of Mercedes & AMG

story-0

6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

 Verdad Gallardo
story-1

Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

 Verdad Gallardo
story-2

Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

 Verdad Gallardo
story-3

8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

 Verdad Gallardo
story-4

Flawlessly Restored Mercedes 190E Evo II Heads to Auction

 Verdad Gallardo
story-5

Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

 Verdad Gallardo
story-6

Mercedes EQS Gets A Major Update: Everything You Need to Know

 Verdad Gallardo
story-7

5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

 Verdad Gallardo
story-8

Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

 Verdad Gallardo
story-9

10 Most Reliable Mercedes-Benz Models You Can Buy Used

 Verdad Gallardo
Old Feb 22, 2018 | 03:49 PM
  #9  
pcy's Avatar
pcy
MBWorld Fanatic!
 
Joined: Mar 2004
Posts: 1,175
Likes: 24
From: Boston, MA
'14 ML350, '13 C220 CDI, '07 C280, '98 ML320
Originally Posted by GregW / Oregon
How many miles on your car when it started leaking? Any idea if there is an internal technical bulletin out? I found a document, LP128-10-P-051935 related to the GLK350 that addresses leaks at the transmission/transfer case joint. I also found this post: http://www.peachparts.com/shopforum/...case-leak.html & this https://www.carcomplaints.com/Merced...fer_case.shtml.
at 31K miles.
I don't understand how they didn't notice the leak during service checkups. Towards the end of last year, as my warranty period was about to expire, I thought I'd check under the truck. After driving the truck on to homemade wooden blocks and removing the belly pan, I can clearly see oil stain on the bell housing, but I couldn't trace the source of the leak. Took some pictures, made an appointment and showed the pics. Tech confirmed the leak and they said the drive shaft seal was leaking. And they gave me a loaner and told me to come back after 3 days. After the drive shaft was replaced, I checked again under the truck. I found the bolts on the cross brace were not tightened (not even finger tight). I think the tech forgot. I took the pics of the cross brace and sent them to service adviser. I tightened the bolts myself. Unfortunately, this is not the first time I noticed something tech forgot to do.
Reply
Old Feb 28, 2018 | 11:54 AM
  #10  
GregW / Oregon's Avatar
Thread Starter
MBWorld Fanatic!
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Jul 2003
Posts: 6,770
Likes: 1,264
From: Lake Oswego, OR
2020 GLE 450; 2023 BMW M2 Coupe
Oil leak at transfer case - 2012 ML350

Originally Posted by GregW / Oregon
Further update: The leak is said to be at the main shaft seal. This does require removing the transfer case. The Assistant Service Manager at the dealership (Mercedes-Benz of Wilsonville) has offered a 50% Goodwill assistance. That's the best I could hope for.
I got the car back yesterday after two days in the shop. Final bill was only $438. In addition to the 50% Goodwill discount, work was billed at warranty rates which reduced it more. So, while this shouldn't have happened, at $1000 off the initial estimate I'm as pleased as possible.
Reply
Old Feb 28, 2018 | 12:53 PM
  #11  
peter2772000's Avatar
MBWorld Fanatic!
5 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2017
Posts: 1,234
Likes: 155
From: Montreal/Cape Coral FL
2012 X6 35i Sport, 2013 ML 350 BT, 2019 4Runner TRD Pro, 2020 CRV-AWD
Glad it worked out for you!
Reply
Old Oct 3, 2020 | 04:34 PM
  #12  
kkarb's Avatar
Member
5 Year Member
Liked
 
Joined: Jan 2016
Posts: 121
Likes: 31
w164
Originally Posted by GregW / Oregon
I noticed oil drips on the garage floor and checked and found drips hanging under the transfer case. It's at the dealer for diagnosis now, but anyone else had this? '12 ML350, 53k mi.

Hello Old thread, but i have the same car, and the same leak. w166 ML350BT transfercase input shaft seal leaking. I went to star dealer and bought the new seal, and was planning to do the jobb my self. Mine had dripped for 4-5 mounts, and i got shock when i googled it should be only 0,5 liter oil in there. But before i started the job i got a good advice from a indy workshop. The advice was to drain the transfercase oil, then add new oil, and mix in 3% off a stuff called Omega 917. This omega product softnes the seal and make it seal again. And as long the seal is not damaged it will be ok again with this omega. I went for the advice, and the leak completely stopped. After about 300km driving the leak was gone. And so far, i has not come back, its completely dry under there. When i drained the oil, it was only 0,2 liter left in the transfercase. This is very scary, because the chain inside transfercase will break if it get to little oil, And total volume only 0,5 liters.

Reply
Old Oct 4, 2020 | 07:45 AM
  #13  
peter2772000's Avatar
MBWorld Fanatic!
5 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2017
Posts: 1,234
Likes: 155
From: Montreal/Cape Coral FL
2012 X6 35i Sport, 2013 ML 350 BT, 2019 4Runner TRD Pro, 2020 CRV-AWD
Thx for posting.

How long ago did you add the 917? I've read that these seal softeners are a temporary fix and that the seals start leaking again eventually.
Regardless, I'd try the treatment as well, if I was faced with any oil leaks.
Reply
Old Oct 4, 2020 | 04:23 PM
  #14  
kkarb's Avatar
Member
5 Year Member
Liked
 
Joined: Jan 2016
Posts: 121
Likes: 31
w164
Hello, it was in july this year. So far dry, no leak at all. Its maybe a temp fix, and I'm not surprised if it starts to leak again. But its worth a try So far, so good If the leak come back, i will take the transfercase down, and replace the seal
Reply
Old Nov 7, 2022 | 11:46 AM
  #15  
joemoe22's Avatar
Newbie
 
Joined: Feb 2014
Posts: 13
Likes: 1
From: ORLANDO, FL
2010 Mercedes GL450
Arrow OMEGA 917

Originally Posted by kkarb
Hello Old thread, but i have the same car, and the same leak. w166 ML350BT transfercase input shaft seal leaking. I went to star dealer and bought the new seal, and was planning to do the jobb my self. Mine had dripped for 4-5 mounts, and i got shock when i googled it should be only 0,5 liter oil in there. But before i started the job i got a good advice from a indy workshop. The advice was to drain the transfercase oil, then add new oil, and mix in 3% off a stuff called Omega 917. This omega product softnes the seal and make it seal again. And as long the seal is not damaged it will be ok again with this omega. I went for the advice, and the leak completely stopped. After about 300km driving the leak was gone. And so far, i has not come back, its completely dry under there. When i drained the oil, it was only 0,2 liter left in the transfercase. This is very scary, because the chain inside transfercase will break if it get to little oil, And total volume only 0,5 liters.
Where DID you purchase OMEGA 917?
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 09:13 AM.

story-0
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-1
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-2
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-3
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-4
Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-5
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-6
Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE
story-7
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

Slideshow: These overlooked Mercedes-Benz models never got the spotlight, but they quietly delivered more than most remember.

By Verdad Gallardo | 2026-04-13 19:35:45


VIEW MORE
story-8
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

Slideshow: A well-used 1991 Mercedes-Benz 300D with more than one million miles is now looking for a new owner, and it still appears ready for more.

By Verdad Gallardo | 2026-04-10 10:05:15


VIEW MORE
story-9
10 Most Reliable Mercedes-Benz Models You Can Buy Used

Slideshow: From bulletproof sedans to surprisingly tough SUVs, these Mercedes models proved that the three-pointed star can go the distance.

By Verdad Gallardo | 2026-04-08 09:55:49


VIEW MORE