WhyAskWhy

Just out of curiosity, for those of you having this transmission problem, do you know which factory produced your car? Was it made in Germany, South Africa, etc.? I wonder if we can find a pattern . . .

TroopH2741

Does anyone have a copy of this service bulletin?

Huz-Z

The car made two rough shifts at low speed and low rpm yesterday. The first was around 5:30pm as my wife drove home, and the second was at 6:09 pm as I was driving the car to pick up some take out for supper.

I called the dealer and left then a voicemail.

rossono308

Did they replace the valve body and reprogram? I had a 2011 prior to the 2014. It was not 4Matic and had zero issues. The loaner I had while the dealer evaluated the issue was an E350 4Matic. It exhibited the same issues to a lesser extent. Perhaps the all wheel drive is the common denominator.


Final assembly shouldn't matter. Engine and trans are sourced from the same factory.

Huz-Z

For my car, it was just a reprogram of the transmission and transfer case. No valve body replacement was done.

Sportstick

As I count it, this was at least the fourth visit for the same problem. If I missed it, I'm sorry, but I believe you should be communicating with MBCA and requiring them to arrange a meeting at the dealership with one of their technical specialists who travel among the dealers. That person has significant authority to direct the activities, such as complete trans replacement, if needed.

Huz-Z

Yes, four visits for this issue.

First time, the salesman drove the car and declared that it was fine.

Second time, the service department "reset" the 4matic system by putting it up on a ramp and letting the wheels spin (that's what they told me).

Third time, they reprogrammed the transmission.

Fourth time (last week) they had the car for the better part of the week and reprogrammed both the transmission and transfer case.

Huz-Z

Hey guys, the service manager at the local dealer is suggesting now that this very harsh shifting is a normal characteristic of the 2014 C300 4matic. Frankly, I think that is bull but before I get irate out of line, what are your views on that?

Thanks in advance for the help!

Josh.A.Hussey

Finally got to the end of this thread.
Lots of good stuff here but I think the bottom line is lazyness.
To SPOT a problem is on the owner (unless its a service) but when there is evidently one present it's not on the owner to diagnose it. That's what we have warrentee's for.
If we had to all diagnose our own issues my mother and grandmother would be driving death traps.

I am from the same city as Huz-Z, actually we are very closely related!
But before we got our BMW dealership Mercedes was the "big kid" on the block and pretty much had control over the majority of the luxury cars around here.

Its not until recently that they've had any competition and they are still doing very well.
As they are the only MB dealership within any reasonable distance they do feel somewhat entitled to judge as they see fit... Even if it means a Salesman making service claims that your car is fine...
(Not trying to accuse anyone of anything but one of my good buddies is friends with the service manager, and I know a few of the techs... And because of this I have a good idea of how the administration is run down there.)

At the end of the day something is definitely not right. I'm going to keep digging but there is no Mercedes Transmission equipped to any of their models (especially not one you pay MORE for like a 4Matic) that is design such that it is so intolerable to drive that people would not want it. No one would buy one, and even if they did it would cause chaos at the dealerships from people thinking they have problems. For a company that has been making transmissions since 1886 this could not be acceptable.

It is a VERY slow time of year for us here in NL, so much so that every year the bigger dealerships layoff as much as 18 techs for the season (which although maybe minor in LA is not minor in NL).
Because of this they are trying their best to save as much coin as possible.
I had a transmission flush done at our dealership that I was quoted 1.5-2hours from 7 other dealerships in Canada and it cost me 3.5hours labour... I know that's BS but I couldn't exactly say anything at this point... The job was done. What I'm getting at is that they are probably neglecting the issue because they are not willing to put up the costs of diagnosing and fixing it. I know MBCA pays for the parts but the time and labour is up to the dealership and they are very busy.
.. I just had another place quote me a 1500$ brake job on a jeep that I can do myself with BETTER pads and rotors for $330. (just proving a point)

Moral of the story as I currently see it:

There is DEFINITELY a problem.
MB St. John's isn't willing to help.
Deal exclusively with MBCA and don't stop until they give you one of the following
1. A fixed car!!!!!
2. A NEW car!!!!!
3. CASH!!!!

rossono308

Now that it's warming up here in Chicago, my car is shifting worse. After everything warms up it does it nearly every 3/4 upshift, downshift. There is absolutely no way someone could convince me this is "normal" ANYONE driving my car would swear off ever buying a MB if this were the case. I can't believe MBUSA would let that happen. I'm pressing on.

Huz-Z

Thanks Josh! I agree that there is no way that a brand new car like a C Class should behave like this if it were operating properly. I only want my car to shift as one would expect a Mercedes should. Not a big ask presumably.

Rossono308 - my local service manager told me that the control logic for the C Class 4matic system is very different between Canadian and American marketed cars and as a result, I cannot cite you as evidence of another owner with the same problem, and vice versa. to me, that is ludicrous but I thought you should be aware of what Mercedes is saying.

I really love my other car which is a BMW that I bought used, but runs flawlessly and gets second to none service at the bimmer dealer here.

Huz-Z

Nobody else has a view on this?????

Huz-Z

UPDATE

My wife just called me to say that she had a telephone conversation with the Mercedes Benz Canada rep for our area (Atlantic) and he acknowledged that Mercedes is aware that other customers are having this very same issue with their Canadian 2014 C300 4matics.

So. Now the ball is squarely in Mercedes Benz' court.

rossono308

MB dealer called an part is in. They ordered only the conductor plate. Apparently in later versions of the 7G-Tronic it is split from the valve body. The conductor plate contains the control unit, solenoids and speed sensors. A little research shows a higher failure rate. I have a scheduled appointment Thursday.

Huz-Z

Hey Rossono308! Good luck in getting this addressed. Please post an update to let me and others know if this fixes the problem - and exactly what they did to fix it.

Like I noted above, my service manager here had the nerve to tell me that this may be normal behavior for the car! Apparently he hasn't read Mercedes Canada's own advertising material which says:

"
The 7G-TRONIC PLUS automatic transmission features lowered fuel consumption, extremely gentle gearshifts and a reduced noise level.

• Seven forward gears: A larger ratio between lowest and highest gears, with shorter intervals from gear to gear to enhance driving comfort.
• Optimum engine speed: The result is reduced fuel consumption and virtually imperceptible gearshifts.
• Prodigious pulling power: Multiple downshifting enables quick bursts of speed.
• New torque converter generation: Less wear, further reduced noise levels and more dynamic response thanks to innovative transmission technology.
• Comfortable or sporty: You can pre-select one of two drive programs: "E" (Economy) or "S" (Sport) for reduced-consumption or sportier driving. On some models, the "M" (Manual) transmission mode can be used for even quicker gearshifts."

From http://www.mercedes-benz.ca/content/...nsmission.html

jimbowmanjr

Honestly I applaud the patience and restraint you have shown.

I seriously doubt I would have been quite as restrained as you have been throughout this process. A used car I could see a few quirks here and there and possibly a few problems. No way would I be understanding if the vehicle was brand new and being handed the excuses you have been getting. I am actually getting more and more nervous about any MB service jobs coming up with the huge inconsistencies across all of these shops. May just end up going all out DIY or Indy shops for the stuff I don't have tools to perform the job.

I actually took my 2009 C300 in for service and was given a 2014 C300 loaner. Truth be told I couldn't stand it and couldn't wait to get back into my own car. Not sure what I will be doing when I decide I want to get another one.

Huz-Z

Thanks. Its my wife's car so I am letting her set the tone, but despite my ample patience thus far, I don't anticipate a pleasant discussion with Mercedes if they continue to stonewall us.

lohseh

Ours does have a slightly pronounced downshift from third to second but not enough to be uncomfortable. There is no clunk or noise so I would also think it is out of the ordinary. We have 2500 miles on ours and I am very pleased with the automobile. It is really fun to drive

rossono308

Picked up my car yesterday PM. So far, I've only driven ~22 miles, none of the annoying problems. The third to fourth shift still seems a little different than the rest of the gears but not objectionable. Interesting note, the loaner I was given was a duplicate of my car (except color). If I was blindfolded I would have sworn I was in my car. The transmission shifted every bit as poorly as mine! I doubt MB would do a recall. Probably deal with it on a case by case basis as people complain. Judging by my experience with the loaner, I'd guess they will have a few to do. I did find a few sites that stated MB was arguing with Siemens VDO, the supplier of the conductor plate, about the failure rate. I would suggest you people in Canada request your dealer to search for a US bulletin regarding replacement of the conductor plate. Good Luck to all and I'll continue to report on driving impressions as I accumulate more miles. I like my car again.

Huz-Z

Hey Rossono308!

Its great news that your car seems to be working properly now. In view of that, I am cautiously optimistic that I can get my car fixed as well. We met with Mercedes' Canadian Field Services Manager yesterday and went for a spin. He noted that he had driven a lot of C Class cars and he concluded that the harsh shifting in ours was clearly very abnormal and committed to getting it fixed for us.

You mentioned a high failure rate on the conductor plate and some places where Merc and Siemens VDO are arguing about that. Can you PM me the links to those sites?

By the way, you mentioned that you like your car again. Well, we have had an awful winter here and the C has gotten us through the worst snow conditions in years with ease (and some clunks). The Field Services Manager told us yesterday that we could disregard the local service manager's advice and use the Sport Mode. So, I did that on a local uphill on-ramp that merges into heavy traffic across our town. I was more than pleased with the very authoritative way that the car pulled ahead of other traffic, while making an entirely satisfying rumble through the exhaust.

These cars are very nice machines - I just need that shifting issue fixed as you have done.

Huz-Z

Any updates, Rossono308?

Glyn M Ruck

The high failure rate of conductor plates is old news from 722.9 transmissions early days & is solved.

Huz-Z

If its old news, why are my local service manager and the Canadian Head Office's Field Services Manager unable to figure out what to do to repair this?

Glyn M Ruck

Unless there is a new rash of conductor plate issues (I have not heard of any) it is likely the problem has nothing to do with the conductor plate. Siemens & Benz had a dreadful fight over the original issue.

Poor shifting can be caused by many things other than the conductor plate but it might be a conductor plate in your case. There is some evidence that Benz has a software issue with some 722.9 Plus transmissions & that there is a fix in the wings.

Huz-Z

Hi Glyn,

In view of the fact that Rossono308 had his rough shifting issue corrected with installation of a new conductor plate, that suggests that these things are creating issues again.

I have been asking Mercedes to fix my car since 19 November - four months have elapsed. I would have been better served to buy a Hyundai Santa Fe; I would get the features, the all-wheel drive capability for winter and far better repair competency from their technical staff. At this point, Mercedes Benz can't figure out how to fix my car.

That is absolutely pathetic.