Vibrations, loud noise, cluncky sounds
03-08-2023, 11:07 AM
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2014 E350, 2020 GLE350
Vibrations, loud noise, cluncky sounds
I have 2014 E350 78k miles. Several months ago I noticed increased vibrations, louder engine and clunky shift switching. Also, if I run above 3..3.5k rpm I sometimes notice burning smell. The car is loaded with features and I would like to drive it for another year or two. I attached a video of switching shift from N to D and than to R. Is it a problem with engine/transmission mounts or something else?
For some reason this site does not accept video from my phone. So, I uploaded it here: https://file.io/vQx6SmcErLrZ
For some reason this site does not accept video from my phone. So, I uploaded it here: https://file.io/vQx6SmcErLrZ
03-08-2023, 02:32 PM
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MY'14 W212 M276 3.5NA @55kMi
mounts + ATF
Sir, I think you're spot on with your engine/tranny mounts diagnosis.
Do you have a service record of transmission oil and spark plugs/boots ?
Do you have a service record of transmission oil and spark plugs/boots ?
03-08-2023, 02:37 PM
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2014 E350, 2020 GLE350
03-08-2023, 03:08 PM
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MY'14 W212 M276 3.5NA @55kMi
no rush...
Add 1Qt of rear differential oil too.
Missed car maintenance can turn into inflated repairs. Transmission ATF filtration is done with a coarse strainer, unlike engine oil. So abrasive clutch particles endup in sludge deposits on valve body screens. All good stuff...
03-08-2023, 05:36 PM
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MY'14 W212 M276 3.5NA @55kMi
improved ownership
The source of increased engine vibration and louder engine is from the weak chain tensioners. They allow timing looseness in the respective trailing camshaft ie. (Driver: intake; Passenger: exhaust) increasing vibrations instead of smooth operation.
VVT has no chance to factor this randomness as the whole VVT gear rotates forward using the chain slack.
Intake Burned Oil :
The burning smell is from quarts of burned engine oil contaminating the intake plenum of the M276.
I don't know other long term fix to protect against valve deposits besides a catch can on the PCV Line.
Dump all the intake oil when replacing plugs with plenum out procedure. There is a small plastic catch can at the front of the throttle body.
Black Oil Color:
The M276 cylinders are designed to save gasoline by not lubricating cylinders below 3,500.Rpm...
Consequently what little oil film is left clinging on cylinder walls gets flashed beyond extreme temperatures. Be sure to use best oil and change it often between 6 to 8kMi. not the recommended 15 to 20kMi!
Last edited by CaliBenzDriver; 03-08-2023 at 06:25 PM.
03-09-2023, 10:04 AM
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2014 E350, 2020 GLE350
Changing transmission/engine mounts, dealing with timing tensioners, replacing plugs, transmission oil. Any expectation for how long the car can drive with all these issues?
I change oil once a year, about 10k miles. full synthetic mobile one.
I change oil once a year, about 10k miles. full synthetic mobile one.
03-09-2023, 01:21 PM
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MY'14 W212 M276 3.5NA @55kMi
maintenance restricted diet
Your car likely will not stop running without warnings... every system will gradually become more disfunctional.
it's only up to owners to maintain what needs attention.
it's only up to owners to maintain what needs attention.
