Wanted to share with you all my on-going battle with my transmission. I have a GLA45 which I purchased in February of 2015. Absolutely love the car and a true joy to drive as a daily. I just turned 5500 miles last week when suddenly I heard a thumping sound from the rear of the car as I was coming to a stop at a light; I actually thought for a second that someone rear-ended me (at least tapped me).

Within two blocks of that, my care suddenly wouldn't up-shift past 2nd gear and the screen indicated: "Reverse not Possible. Service required". I immediately pulled over and shut the car off and upon restarting everything seemed fine. Later that day it happened again 3 times in a row.

I parked the car and took it to MB service the next business day. Two days later they called and said my car was ready for pickup. They told me that they needed to clear the memory and download a new version of the transmission software.

I jumped on the highway to head home and within two exits, same thing happened. So I turned around and limped back to service. I was really nervous because when this happens it gets stuck in "C" mode and only shifted between gears at a really high RPM (almost red-line).

The following day the service department told me that they couldn't figure it out and had to engage MB Engineers. Today they called again and said the MB engineers requested that they replace my entire clutch and that it would be shipped by next week.

Now I'm really concerned that it will never be the same again because the service manager told me that in order to replace the clutch they must remove the entire engine in order to separate the engine from the transmission, so that they can get to the bell housing.

Anyways, bit of a nightmare for me and I'll let you all know the results...also curious if anyone else has had to have their dual-clutch replaced?

Update.....
They replaced the dual-clutch and informed me that it did not solve the problem. Now they are shipping a new transmission control unit, yet another week without my car...I joked with them, asking if they were going to pay my July payment being that my car has been with them for almost the month of July.

 

Are you saying they are replacing the transmission or are they going to disassemble it and replace the clutches? I'm used to P cars and BMWs where they don't work on the DCTs at the dealership, they just swap em.

 

No, the service manager specifically said they are installing a new dual-clutch and that they must separate the transmission from the engine...but to be honest I get the feeling he is just feeding me information that he thinks I might understand instead of the truth, because he said the "bell housing" as if its a traditional clutch.

If they do in fact replace the clutch, I wonder if I should break it in???

 

I still think they may be saying they are swapping out the "dual clutch" transmission or DCT, in other words the entire unit. That would be preferable to me over having them pull it and then do the R&R of the clutches in the transmission.

Either way you will have some break in to do, clutches break in quickly, gears take more time and benefit from heat cycling in the early miles.

Keep us up to date and hang in there, a lot of us have been in similar circumstance and it isn't any fun but usually it works out ok.

 

I agree, MB doesn't replace clutches primarily for the same reason they don't turn AMG Brake Rotors but replace. The entire unit will be sent back to MB AMG for inspection and determination of failure.

No biggy, everything will be just fine once it's replaced. MB takes this type of failure quite personally and is a direct hit against their efficiency ratings. Typical German mentality and ideology.

 

Any updates ?

 

Hi - I have a 2015 GLA45 AMG (11,000 km like 5,000 miles) and the transmission started to make the same knocking sound when going into neutral. It is very odd and definitely not normal.

My car is currently at MB service to check this issue and I'm curious to know what they will say - I hope they don't come back to me saying all is normal.

Do you have an update on the issue? Did MB solved it?