Mercedes CLA Forum banner

1 - 20 of 22 Posts

·
Registered
Joined
·
76 Posts
Discussion Starter #1
Has any of you had any problem(s) with the rear differential. Mine is a 2014 cla250 4matic and the rear diff makes a terrible clunking/clicking noise when slowing, accelerating and turning. At constant road speeds it is quiet.
I plan to put my GoPro under rear to see if any thing is moving or to hear it better but haven’t had the time.


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
314 Posts
Has any of you had any problem(s) with the rear differential. Mine is a 2014 cla250 4matic and the rear diff makes a terrible clunking/clicking noise when slowing, accelerating and turning. At constant road speeds it is quiet.
I plan to put my GoPro under rear to see if any thing is moving or to hear it better but haven’t had the time.


Sent from my iPhone using Tapatalk
This has been documented in other posts. You probably have a failed rear diff, which requires replacement.
 

·
Registered
Joined
·
607 Posts
….I plan to put my GoPro under rear to see if any thing is moving or to hear it better but haven’t had the time.
Great Idea! Don't forget to upload for us, if possible.
 

·
Registered
Joined
·
76 Posts
Discussion Starter #4
This has been documented in other posts. You probably have a failed rear diff, which requires replacement.
Thanks, I’ll search for those posts. I guess it cost a fortune to replace.
Do you know if it can be rebuilt or does it have to be replaced?


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
510 Posts
Thanks, I’ll search for those posts. I guess it cost a fortune to replace.
Do you know if it can be rebuilt or does it have to be replaced?


Sent from my iPhone using Tapatalk
I am pretty sure replaced or second hand. You can disconnect a connector I believe and will disengage it. But then you are just fwd.


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
76 Posts
Discussion Starter #6
I am pretty sure replaced or second hand. You can disconnect a connector I believe and will disengage it. But then you are just fwd.


Sent from my iPhone using Tapatalk
If this unit is only good for 50k miles or so I surely wouldn’t want a used unit.
So, you speak of a wiring connector?
Does the driveshaft need to be removed to test this?


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
510 Posts
If this unit is only good for 50k miles or so I surely wouldn’t want a used unit.
So, you speak of a wiring connector?
Does the driveshaft need to be removed to test this?


Sent from my iPhone using Tapatalk
I don’t think so I think it just disconnects the electronic bits to tell it to move power to the rear diff. There is another post on this.


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
510 Posts
From another thread.

Hi All,

First time on here...and man have I had problems with this car as well. I've got all the typical rear diff issues, but no modifications etc were made beforehand. No changes to anything. It started popping up on my wife's 2014 CLA a few months back and she kept driving it without telling me. Of course, it happened right after the warranty was done and Benz refused to do anything about it. I've seen service bulletins released about this that say to remove the sensor that tells the diff to engage/disengage for better traction. If the issue disappears, the bulletin says to replace the whole part. It's typically replaced with a remanufactured part. I was quoted about 6500 CAD - the car is barely worth 20k in perfect condition so this repair is difficult to justify. I had an independent shop remove the sensor and problems were gone - so definitely the differential. This sound / vibration is unholy. I had all 4 wheels straightened and checked for bends just in case they were contributing as well.

Since it was disconnected however, the car's acceleration, performance etc is way better. It now drives like it looks. I haven't bothered getting the diff replaced. What do you guys think? Anyone know if it'll cause any harm not replacing it? Essentially it's running on front wheel drive like a non-4-matic no? I'm thinking about just throwing on good snow tires and driving it until it's dead.

I'd appreciate any thoughts on this. Am I causing any additional harm to the car?

Thanks!


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
314 Posts

·
Registered
Joined
·
314 Posts
Wow
So many rear diff posts ... a class action may clear things up and extend warranty for the diff
They seem to fail after 50,000 miles or so. My guess is that many of the 2015s aren’t quite there yet. Eventually, I think it’ll be the “known problem” that will plague the Gen 1 CLA/GLA’s reputation. Being that it’s such an expensive repair and doesn’t directly impact safety, I doubt MB will warranty it voluntarily. They need to figure out a fix that doesn’t require an entire diff replacement.
 

·
Registered
Joined
·
76 Posts
Discussion Starter #15
This really irritates me because I ask my dealership what the noise was and they would not even acknowledge that it made a noise. Told me nothing was wrong with it!
Seems that they would have tried to make that money.
The thing I don’t understand is that they sell re-manufactured units. If they can be rebuilt, I can rebuild it if the parts were available! I knew there was a reason I always avoided these POS Mercedes cars!


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
9,873 Posts
Cheapest (out of warranty) fix is to disconnect the control harness drive to verify problem is isolated get a preowned diff from ebay or reman unit from certified shop or online dealer swap diffs but leave disconnected then find indie or online benz tech service and code/learn it back into the system.
But factor in tools and diy time plus coding might just be a wash at a good indie shop.
 

·
Registered
Joined
·
76 Posts
Discussion Starter #17
Cheapest (out of warranty) fix is to disconnect the control harness drive to verify problem is isolated get a preowned diff from ebay or reman unit from certified shop or online dealer swap diffs but leave disconnected then find indie or online benz tech service and code/learn it back into the system.
But factor in tools and diy time plus coding might just be a wash at a good indie shop.
Sorry for sounding stupid but what is an indie shop?


Sent from my iPhone using Tapatalk
 
1 - 20 of 22 Posts
Top