Thank you so much brother, going to get fluid changed in mine. Very professional and slow paced video. Thank you for your time and effort as well to share here.

I had the same problem on my A250 sport 4matic 2016 with 100 000 km on it. Thanks to this video I asked the dealer to just change the oil in rear diff and so far the problem is solved, car feels great in corners now and the little kick once stopped by the traffic light also dissappeard. I will update if problem comes back. Paid the dealer 144 eur for this job. Thank You for information in this video, saved me time and money.

I really like your commentary, very interesting. Thanks for creating.

Reminds me of symptoms and soulution using Honda dual pump fluid for rear diffs. Keep up the good work.

Really such fast and all-comments-responded is a reason to thank you in particular.

Great diagnostic sir. that really a good education for me,thx

thank you for sharing and nice diagnostic technique !

Thank you for your video. You saved me bug $$$$. Merc suggested to replace the differential.

I have a 2018 cla 250 4 matic and had the same issue, I changed the oil like you said and noise went away completely after 2nd day of driving around. Thanks for the advice and saving me big bucks at the stealership. There diagnostic was expensive and they wanted to change out the whole Differential without even trying the oil. BTW oil needs to be changed after 30,000 miles regardless as part of matenance.

I have a 2016 gla45 that I’m about to buy a new differential for but I have already changed the fluid and reset the codes but I still have the noise and also get a “4matic unavailable” signal when I launch it

Hallo, ich hatte das gleiche Fehlerbild! Auf dem Rücksitz kann man es beim mitfahren sehr gut in seinem Hintern merken. Fühlt sich in etwa so an als wenn man gegen die Bremse anfährt und diese sich mit leichtem knallen löst. Nur nicht so blechern. Öl habe ich selber getauscht Motul 75W 140 Arbeitszeit in etwa 1/2 Stunde und nach einer am Anfang ruhigen Probefahrt ohne anlernen im Allrad Modus und zu erst stärkerem Fehlerbild für etwa 5 min hat sich eine Normalisierung eingestellt und nach 1/2 Stunde war alles ruhig!

Afternoon thank you for sharing. do the noise go away as sooner you change the oil or have to be driving it for a couple of miles?? my 2018 have the noise whenever i turn and exactly what you described send to change the oil but i was told i have to drive it for about 500 miles to check it and make sure it work. any idea?

Any idea where the tire monitor is at (modules)

Thank you for sharing such techniques. Really appreciate. Kindly could you share the technical sheet of this diff?

What mileage was on the vehicle when it came to you? It's crazy. that Mercedes-Benz do not specify any fluid changes on the maintenance schedule for the CLA250 4MATIC but they do state an interval for the CLA45 4MATIC. Never heard of a car with a rear diff that wouldn't't require a fluid change yet Merc state it's lifetime fluid.

great video thanks for the info just ran into this at my shop. not much info available on these cars. this also applies to infiniti qx30

Hello, I had the same error picture! In the back seat you can feel it very well in your butt when you ride along. It feels like you're hitting the brake and it pops off. Just not so tinny. I changed the oil myself Motul 75W 140 working time in about 1/2 hour and after an initially quiet test drive without training in all-wheel drive mode and only a stronger error pattern for about 5 minutes, a normalization set in and after 1/2 hour everything was quiet !

Great job man

Thank you, thank you , thank you, really thank you... you know how much money I save my self... i bouth the mercedes oil, it was a 105dllrs a quater they told me it takes two and some onces, so i bouth only two but in reallyty takes half a quarter... a soon I change it the noise when off... yessssss tomorrow i will return the other quater to the dealer

You Save me, i have a CLA 2017, I have the same annoying noise and I think I have the same problem, it has been heard for about 3 months, no mechanic advised me to change the oil!

Thanks for showing the chassis ears in use for this diag, Sadel. I'm curious what the mileage was on the rear differential fluid and what service interval Mercedes recommends for it? Thanks for sharing your skills with us in another great video, Sadel!

Thankyou for helpful video

I have the same problem I will be taking the car in for them to look at it and will reference your video . By the way is it also possible to dis engage the seleniod were the noise goes away and the car operates as a FWD

❤❤ Thanks a million

at what speed do you have the problem? i have a similar problem knocking noise only if I am at speed of 0-25mph, in drive mode D1-D2-D3 
 Both if I accelerate, and if i don't accelerate or break. the noise increase in frequency if I turn right or left. no knocking noise in neutral and rear.

Can you tell my what type of fluid this is so I can get mine replaced? I'm having same issue.

Thanks for sharing great techniques applied.

Same problem, what is the specs of the oil I should get do do this on my 2014 merc 4matic gla 220

Hello i have the same probleme in my gla 220 cdi 4 matic A little kick once stopped by the trafic i change the oil but the problem is not solved The dealer said that i have to change the oil a seconde time to solve the problem What is your opinion ? Help please

Great diagnostic sir. I am curious, as someone who is always working on different brands, (you could think of me as an independent) how do you charge fairly to yourself and the customer on an issue like this? I am always curious about the business side of being an owner/technician and wonder sometimes if I had to change up how I make a living, could I make it on my own? Is it a case of I charge X amount per hour and you pay for however long it takes to find the issue? That seems fair to me, but customers tend to distrust people in our trade. I have been out of the public service game for 20 years, and I honestly don't know . I maintain a fleet of heavy equipment and light duty trucks for a company, so I never have to worry about customer relations (except for my equipment operators). Anyway, nice catch and I hope to see more and more of these in the future.

Was the noise just a knocking or a whinning noise? as mine is whinning but MB is clueless or seems it so far.

Thx for the vide m8

Where are you located. i need my car looked at.

I want to delete de rear diff and driveshafts to make it fwd only. I never had awd even the crvs i had back in the day i deleted them instead of replacing the rear diffs... Do you think its doable on these cla. Im thinking of leaving the diff selenoid plugged in so the computer still sees it instead of trowing error code? Need your input on this... Do the rear axles go thru the wheel bearings? If yes i will just leave the outter part of the cv joint there to hold the bearings together just like i was doing with the crvs.. I paid low money for the 4matic. I love fwd better. Thank you!

what or oil used for a rear transmission?

Hi there excellent diagnostic. Can you tell me your location so that I can get me fixed by you. You know your stuff so well. Thanks

I have changed the oil but still the noise is still there can you pls help me

Hi, Do you know if the GLA 220 cdi has the same differential?

Is there a contact line where I can contact you?

I have just disconnected the 4matic socket from the rear differential to save it from further damage, before changing the oil… Hope to change the fluid soon. Now the 4matic is just a FWD

hi! Is this diff the same as I have in my 2014 gla 220d 4matic? Got a call from my mech saying the clac clac noise when turning the steering (in movement) is coming from the diff.. he just talked about replacing it, not changing the oil… would it work in this case? Thank you

Where do you live? Can you help me?

I have a CLA 250 Sport 4Matic, corner and accelerating when standing still gives a pounding sound from the back. Will this perhaps fix my issue?

I have the exact same issue with a 2015 GLA

Español te explico si andas buscando que tu mercedes hace un ruido que truena y no saves porque ... usualmente los allwelldrive hacen ese ruido enfadoso... cambiale el aceite del diferencial pero ponle el original que vende el dealer y en cuanto se lo cambias el ruido se va.... garantisado.. ya que el aceite se adelgasa demasiado y pierde su viscosidad es por eso que el ruido se wscucha mucho cuando esta frio, pero el nuevo haceite tiene todo la viscosidad nueva que luego luego empiesa a trabajar.. esto ws por si

I bet this is the same thing that my 2014 cla 4matic has right now!

Afternoon thank you for sharing. do the noise go away as sooner you change the oil or have to be driving it for a couple of miles?? my 2018 have the noise whenever i turn and exactly what you described send to change the oil but i was told i have to drive it for about 500 miles to check it and make sure it work. any idea?