ML350 bluetec 2012 (HELP)
We purchased the 2012 Ml350 as a certified pre owned with 32k on it. The vehicle has been great for the first year and half and after that it's been a nightmare .
just outside of the warranty expired the vehicle started leaking oil in the driveway, we visited the dealership and it turned out to be the oil cooler seal according to the service center,
Mercedes gave a quote of 2k-2500 to repair and then changed it to 3600 .
We got a second opinion for verification and received same diagnosis with price slightly lower but felt more confident with the dealership due to a 2 yr warranty.
The repair went from a 3 day job and turned into a 15 day job with no explanation from the dealership other than to say they had a problem with a bolt and wanted to add
another 500 to the job after not contacting us to provide any pre estimate or update. Several call were made to them through course of service with no update or return calls.
We picked up the ML and its seemed fine for 8 months no issues or leaking. The ac however has been working intermittently on the drivers side.
Something with the damper I believe is cutting off the air on the drivers side but then returns to normal.
Moving forward to 2 weeks ago , my wife was on her way to work and the car started to smoke she turned the ac off and the smoke went away, She smelled an electrical burn.
She took it to the dealership expressed her concerns and they looked at it and stated there’s a minor leak in the transfer case output shaft seal and the ac is probably just low on
refrigerant. They suspected oil from the transfer case dripped onto the exhaust and smoked a little? The smoke emitted from the passenger side and then stopped when she turned off the ac.
We have not seen any oil stains in driveway and we have a driveway with no stains.
We bit the bullet and agreed to a 2000k repair, I was told in the beginning the repair cost was high because they had to drop the transmission.
They made the repair on the 22nd of April, we picked it up and noticed the next day a thunking noise on initial acceleration from a stopped position.
We returned the vehicle to the Mercedes service and now they have stated we need motor mounts. We were quoted 1500. and now 1800.00 plus tax but mercedes
will pick up most of the cost and we get to pay $500.00
They have had the car now for more than a week first due to parts being delayed, then they needed the transmission mount and now it needs exhaust clamps?
Does this sound legitimate? Still no car and more discovery or maybe they just don’t know whats wrong with it and are just guessing at this point?
Im sending another email to MBusa but they declined any goodwill assistance on the oil cooler leak, transfer case leak and just now they are helping with this repair.
We have put 7k in repairs in less than a year and are dreading if anything else goes wrong.
It seems like the 2012 Ml350 is plegged with issues and should be considered a LEMON.
Any advice would be greatly appreciated.
Last edited by southflorida69; May 4, 2019 at 02:10 PM. Reason: adding photos
I'm of no help when it comes to your issue, but the people in the W166 section might be able to help you out. Repost your thread there and you may get some help.
https://mbworld.org/forums/m-class-w166-149/
We purchased the 2012 Ml350 as a certified pre owned with 32k on it. The vehicle has been great for the first year and half and after that it's been a nightmare .
just outside of the warranty expired the vehicle started leaking oil in the driveway, we visited the dealership and it turned out to be the oil cooler seal according to the service center,
Mercedes gave a quote of 2k-2500 to repair and then changed it to 3600 .
We got a second opinion for verification and received same diagnosis with price slightly lower but felt more confident with the dealership due to a 2 yr warranty.
The repair went from a 3 day job and turned into a 15 day job with no explanation from the dealership other than to say they had a problem with a bolt and wanted to add
another 500 to the job after not contacting us to provide any pre estimate or update. Several call were made to them through course of service with no update or return calls.
We picked up the ML and its seemed fine for 8 months no issues or leaking. The ac however has been working intermittently on the drivers side.
Something with the damper I believe is cutting off the air on the drivers side but then returns to normal.
Moving forward to 2 weeks ago , my wife was on her way to work and the car started to smoke she turned the ac off and the smoke went away, She smelled an electrical burn.
She took it to the dealership expressed her concerns and they looked at it and stated there’s a minor leak in the transfer case output shaft seal and the ac is probably just low on
refrigerant. They suspected oil from the transfer case dripped onto the exhaust and smoked a little? The smoke emitted from the passenger side and then stopped when she turned off the ac.
We have not seen any oil stains in driveway and we have a driveway with no stains.
We bit the bullet and agreed to a 2000k repair, I was told in the beginning the repair cost was high because they had to drop the transmission.
They made the repair on the 22nd of April, we picked it up and noticed the next day a thunking noise on initial acceleration from a stopped position.
We returned the vehicle to the Mercedes service and now they have stated we need motor mounts. We were quoted 1500. and now 1800.00 plus tax but mercedes
will pick up most of the cost and we get to pay $500.00
They have had the car now for more than a week first due to parts being delayed, then they needed the transmission mount and now it needs exhaust clamps?
Does this sound legitimate? Still no car and more discovery or maybe they just don’t know whats wrong with it and are just guessing at this point?
Im sending another email to MBusa but they declined any goodwill assistance on the oil cooler leak, transfer case leak and just now they are helping with this repair.
We have put 7k in repairs in less than a year and are dreading if anything else goes wrong.
It seems like the 2012 Ml350 is plegged with issues and should be considered a LEMON.
Any advice would be greatly appreciated.
The cpo would have helped a lot with bluetec diesel issues.
Unfortunately, you have a lot of issues still ahead of you.
The best bet for the long term is to get a tune from green diesel engineering or one of the other companies recommended on the diesel forum.
You'll have to find out and decide which parts you want wanted deleted or tuned out.
If not, and the residual is good. Yiur best bet will probably be to get out early. Perhaps mb or your dealer can give some trade in assistance against another cpo model.
About your sprinters. Best to extend any factory warranty if stil applicable, try to cut in half the reccommend oil change interval, perhaps invest in a oil catch can, and look up the larger oil filter kit.
Trending Topics
http://www.stephensservice.com/bluet...ssuesproblems/
Please read this, it will give some clarity to the issues you are facing.
Also it will help prevent any catastrophic issues you might face with your sprinters, as they are vital to your business.
Again, if you have any questions please do reach out to us; and for more specific diesel advice the diesel forum is great!
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I'm also an HVAC contractor up in Montreal and I have a place down in Cape Coral FL.
As kombifan stated, up the oil change intervals. Read the info in the link he posted as well. Lose the engine covers and belly pans on anything diesel. Do the deletes and reduce the odds of future issues, though you cannot undo what's been done.




