Why don't the idiots change the conductor plate & flash the calibration data from your old TCU to the new one. Each valve body is flow benched & the calibration data loaded to the TCU.

It's not a big job to change a conductor plate. It least that would eliminate the conductor plate if the issue continues.

Your guess is a s good as mine at this point. I am so frustrated!!

I too have the same problem with my new 2014 C300 4Matic. It went back to the Dealership last week and they were told by Mercedes Benz to reprogram the TCU. It made no difference to the problem. It has now gone back to the Dealership again and they just called to tell me that Mercedes Benz informed them that a Software update is in development and that in the interim they are to replace the Valve Body which will hopefully help temporarily until the update is available. It looks like we may have a permanent fix on the horizon, fingers crossed.

Thanks for that. I've also heard a software fix is in the wings. Let us know what difference a new valve body & conductor plate makes.

The 2014 C300 is the exact same as the 2013 C300, in terms of hardware, in the U.S. anyway. Since 2013 cars are fine, why not just apply the 2013 TCU/ECU settings to the 2014s and be done with it?

Dealership called. They replaced the Valve Body and Conductor Plate. The problem was still apparent on the subsequent test drive. Once again waiting for input from MBUSA as to how to proceed. Beginning to get sense of humor failure.

Just heard back from the Dealership. MBUSA want the Transmission replaced.
This is on order and will hopefully be here in a couple of working days. Watch this space.

Folks

I have had mbusa buy back my custom ordered 2014 e550 that does the exact same thing as your c300 vehicles... See my sig

My replacement e550 does the same thing!!

In the previous 2014 e550 they replaced my valve body and the 4/5th gear clutch pack ... Problem fixed for a while then started coming back

What an ordeal

I am not truly confident that my replacement Transmission is going to be the end of my ordeal either. Your experience Peter, kinda supports my thinking on this. We'll see how my vehicle performs when I eventually get it back. I will naturally keep this thread updated.

Pete T.

I am experiencing the same symptoms following the Transmission replacement.
It is, if anything, marginally worse.

Thus far, the Dealership and MBUSA have been very responsive in seeking a resolution to this anomaly, sadly with no success to date.

The Dealership has now been informed of the continued problem following the Transmission replacement as has MBUSA Tech. I have also contacted MBUSA Customer Service Dept.

What next? I await their next move/decision.

Excellent car, unacceptable Transmission.

I have same issue on 2014 GLK350. It is a calibration issue. I'm a retired automotive engineer and this issue can be found on many vehicles. It requires the calibration engineer to change the software. Until MB releases a revised calibration we will have to live with this issue.

Took my 2013 C250 in for Service A last week and got a 2014 GLK350 loaner with 5K miles that had the same problem. The clunky shifting and dead spots in the steering made that car horrible to drive. Couldn't wait to get back to the C250.

The word on the street is that the new software is planned for a May release.
I wonder if this will be the panacea we are all hoping for.