Swoosht04

OK so this car has been making a noise which to me sounds like a bad bearing in the rear. I have a buddy who is a master Mercedes mechanic who told me it could be motor or tranny mounts. Although he is 800 miles away so he can only suggest. I took to it to a local shop who put the car up and pointed to the tires immediately. So I replaced all the tires with Michelins and I still here it. I was going to replace the Diff fluid to see of that helps but my gut is still telling me the rear bearings. I know somebody's idea on a noise is not what another person thinks so my question is this. Is this an issue with a 2011 E350 not 4 magic with 69K miles. At one point it may have sat on a lot for a bit not being driven normally. Not sure if that make a difference or not.
LmK.

Plutoe

If you think it's a manufacturing issue, you can always call a dealer and ask if the are any differential "TSB" on your VIN!!

Other that that put the car on a lift and try and duplicate the noise--that will help in locating the source!!

dbldpr

I have a 2014 E350 4matic sport. I heard a humming noise from the rear of car when driving on long trip at high speed. I installed sound deadening material on inside of trunk where spare tire is. It took care of the humming noise. These cars are poorly made for sounds. You hear everything.

thenew3

Must be isolated to 2014. My 2013 E350 is so silent, I can hear my baby breathing in the back seat when we're going 80 MPH.

OP: If you have a trusted mechanic near you, you can have them take a ride with you and see what their opinion is.

dbldpr

There has been several threads on this forum about the humming noise in the 2014. Nothing under the car is insolated. You only have a cheap piece of felt on both sides of the car and in the rear wells for protection. Does nothing and cannot be cleaned. If it was plastic at least it could be cleaned but the felt cannot be cleaned. If you run over new paving it will stay that color white or yellow until the dirt covers it up. My drivers side front wheel barring went out at about 1000 miles. My navigation will not let me put my address into it. It says I live 10 miles from where I actually am. IN 2014 they switched to Garmen for the head unit My 30 navigation system will take my address but the $60,000 car will not. The transmission has jerked between the 2nd and 3rd and 5th to 6th gear since I received the car. It has been in several times to get reprogramed but it only lasts for a few weeks and goes back to the old routine. MB is aware of the problem but has not found a fix, If you put garbage in you get garbage out. The 2013 and before cars I can put my address in but not in any 2014 model. .Had I known what I know now I would never have bought the car But I am used to the flaws now so I will hold on to it for a while

mleskovar

Why don't you take out the fill plug and check to see if there's any fluid even in it

KEY08

What do you really think, dbldpr? Haha! That ooga should put a smile on your face no matter what issues you have!

dbldpr

You are right with the ooga horn all worries go away. Don't get me wrong I love the car I just hate the flaws that could be fixed but MB does not care.

beejAMG

reminds me of a story i read a while back.

a lady goes to an indy and complains about the noise in her boot. writes on comments....
"makes a loud thud on the right side when i turn left and a loud thud on the left side when i turn right".

comes back after an hour and the diagnosis on the print out read....
"remove bowling ball from the boot".

OP: hope you find a fix to your problem soon.

KEY08

Hilarious!!!

Swoosht04

Well I will be replacing the Diff fluid because I really think it is NOT a bearing issue. If I am driving I can put the car in Neutral and the noise goes away. All you hear is your average road noise and what not. Only when I put it back in Drive do I hear it. I am not sure if I have the Hex to remove the plugs so I will have to run to my boys shop when he has a lift open. I will let you guys know what I find in the Diff.

mleskovar

Probably not your differential then. Transmission output shaft bearings have been known to go and cause your symptoms.

Swoosht04

Where is this bearing? Does it necessitate transmission removal or just drive shaft?

mleskovar

I've never done/seen it, only read about it. Do some searching....there's also reports of driveshaft center bearing and differential pinion bearing causing noise? Under load the noise can be from anywhere.

Tpat859

I have a 2010 C300 with 55k miles on it and I'm having the same problem with rear end noise. sound like bad bearings to me. Any suggestions?

shak

OP, did you ever figured it out?

I have 2012 350 with 75k miles, and now hearing some humming noise, not really sure if its from the rear or the front, its kind of coming from under the car. The noise is consistent at around 60mph, I ruled out the bearings as bad bearings will get louder the faster you go. If I go 80, I don't hear anything.

I was putting the blame on my rear tires, usually bar driveshaft, rear diff, bearing, the sounds will increase with the speed.

I guess I should slap a pair of new continentals on the back and go from there.

Swoosht04

I have not had a pro look into it. But I really think it is the output shaft bearing in the tranny or the tranny it's self. Try this. Drive down a street with nobody behind you and shift the car into neutral. If the noise goes away (as in my case) then you know its something in the tranny.

shak

I did, the noise is still there. Not even sure if its coming from the front or back, and its loudest at 60 mph, anything faster it goes away. Usually bearings or any gear related noise will increase with speed, so I dont know.

I had a similar howling back in my M45, set of new softer tires fixed the issue.

oogurkan

Hi all,
I have exactly same problem. I tried shifting to Neutral on the road, nothing happened.
I have Michelin PS4, 2 years old, 3,5mm thickness. And the left/right covers under the car has been changed 2 days ago. But the sound still there. Is this a basic tire issue, should I replace the tires? Please help, thanks in advance.

oogurkan

Last weekend checked with mechanic, made a test drive together: yes there is a noise. Then lifted the car and checked wheel bearings fronts rears, all clear. But the tires finished almost. Final decision what mech said was that my tires causes noise.

Arrie

Tire noise does not go away with speed increase up from certain speed, if your problem is the same as the one you respond to.

If you have a noise that gets worst at some speed, i.e. is less below and then also above certain speed you have a vibration resonance issue. On a RWD car the FIRST thing to check is the drive shaft from gear box to rear differential. It could be a balancing issue or a problem with U-joints of the shaft.

oogurkan

Thanks for information.
- The noise does not goes away or does not get worse. Only frequency follows (increases) the speed.
- There is no vibration at all.
- I shifted to N while driving at certain speed and the noise was there. Noise level/freq does not change with shifts.
- Acceleration (or decl.) was not affected the noise.
- I did the Slalom test and has no affect on noise.
- Brake pedal has no affect on noise.

I am planning to change my Michelin PS4 tires. Then we will see.

Arrie

My post was based on your first post where you said "I have exactly same problem" where you replied to shak's message where he said "Not even sure if its coming from the front or back, and its loudest at 60 mph, anything faster it goes away.".

Now you say the noise does not go away,

And for your info, all noise is vibration.

oogurkan

Sorry for misunderstanding.. This is the last status for me. Thanks for reply.

aquasition

My 2016 E350 wagon started to show a humming noisr from the rearend and It was being caused by a serious delaMination on the rear drivers side tire Car is little over 43000 miles now
I mean serious! Wires and chunks coming apart
replacing both rear tires today and I am certain noise will go away
check your tires!