FINALLY fixed the common TRANSMISSION rough up/down shifting in W222!!!!!!!

As you know, this has become a common problem and many of you might even have it without knowing it. The W222 should shifts way smoother than it currently shifts for almost all of us.

I took my car last weekend to the dealership and said, I think my car shifting is rough especially from 2-3 or 3-2 and between 5th and 4th gear. Luckily I ended up with a smart engineer how had something other than the standard response (this is how it's designed, normal). This time, he agreed that yes it should be smoother, I have a solution, give me 1-2 days.

He called 2 days later and said, hey your car is ready. it's day and night difference now. The car shifts much smoother than before, even smoother than when it had 0 miles on it, an believe it or not just as smooth as the new S560 with it's new transmission. According to the engineer, what he did is that he installed two customized software, one for the transmission system in general, and the second is by connecting a computer to the car as it's being driven and a computer would adjust the shifts points to an optimum values (rather than a pre-adjusted values).

Conclusion, I knew from the beginning that the rough shifting the all 2014-2017 W222 cars are seeing is not due to a hardware or design issue, it was due to a software-and-design communication issue and wrong pre-adjusted shift points. Apparently, if you end up with a smart service manager who can connect your car to a computer that can automatically adjust the shifting points of your transmission to whatever is optimum for your car along with the new transmission software then this is all what it takes to change this very common problem. Just go to the dealer and try to skip service advisors and talk to the engineers directly (they might tell that's not possible, but just ask them to get you in touch with their most senior service engineer). Service advisors may not be the right person to talk to.

Update: here is a screenshot of the service comments (the detailed feedback i wrote above is based on discussion but it's summarized in the service comments below).

 

Good to know. I already wrote off the 5-4 rough shift to the obvious big leap in gear ratio from 4 to 5. It seems bigger than the rest.

 

Mine is shifting like ****...Random jerky downshifts and what not. I need to drop off for a few days and let them diagnose as well.

 

Hello,

Likewise, car is jerkily lurching and abruptly shifting around 20-30 whenever it goes from 5 to 4 and 3 to 4.

I don't know if I need to do another transmission learning reset or just take it to the dealer.

It always seems like a hassle to convince a dealer to look at an any more than slightly complex computer problem.

... There has to be a TSB for this by now and we shouldn't haven't go to the dealer for a 'beat-around-the-bush' appointment of a problem which "wasn't replicable" or is "normal behavior".

 

I am also adding here the service comments (the detailed feedback i wrote above is based on discussion but it's summarized in the service comments below).

 

It would be great if they actually found a fix. I hope they didnt just do a transmission reset and that problem will recur shortly.

 

No, it's not a transmission reset. We tried that last week and didn't work for more than 1 day.
For this latest service, as I mentioned (and as shown in the service paperwork attached in my 1st post), they did two things:

1. a new SOFTWARE was downloaded
2. Then a computer was connected to the car to adjust the shift points of the transmission while it's being driven (also called transmission shift normalization).

As I mentioned, the car drives different as night and day. Not only it doesn't do jerky shifts now, but it also drives way smoother and you can't even tell when it shifts from gear to another. Even when driving in Sport mode, it's so smooth when it shifts.

 

Good to know that the rough shifts can be addressed via TCU software, meaning the problem is not inherent to the mechanicals of the 9G transmission.

 

The confusion around this issue is just crazy. Believe it or not, I've asked my local dealership about this issue and they were telling me "yes we know, it's a software issue but Mercedes engineers are still trying to develop a software solution). I couldn't believe that, so I drove 1 hr to the nearest other MB dealership at a nearby city and as you can see above, their response was the same except that they said (and we also have the software and the PC tool to do shifting normalization). Clearly there is no official notice or reference for Mercedes engineers or service managers to look at online, it's only a matter of luck of you finding the right service engineer who has the software and a computer tool and knows how to use it to normalize and adapt the shift points!.

 

My dealer did the software update and the two person manual shift point normalization. It worked for about 5 days. They are trying again now. More to come.

 

Make sure they use the software dated June 2019, not the last one that was released end of 2016.

 

Thank you, I'll verify that's what they did. Hopefully yours will continue to perform. I was so upset after mine worked flawless for about a week then regressed back to the same problem.

 

My 2015 S-600 shifts beautifully.

 

Different transmission I must assume?

 

My previous w211 and w212 shifted like **** as well (2-1 jerk). Too bad they can't get it right like with BMW, which are smooth as butter. I wont settle for a S shifting like the way it is now. The other day it slammed while downshifting - I won't rest until it is fixed or warranty replaces the trans. Fluid is new so no excuses there..

 

Exactly, fix it or I am abandoning the brand all together. This isn't some used C class, I paid a lot of money for this car.

 

Had the slam downshift happen only once after they did the update. Question, how are you getting the 2 to 1 jerk, I assume you are driving in Sport Mode often. If you are not in sport mode, trans starts in 2 not 1, so it will never go to 1 unless your in sport.

 

I only get a nasty 5 to 4 downshift, everything other scenario is flawless.

 

Yup, I'm with you. Fortunately, I have good relation with my SA and Tech so I hope it can be resolved soon. I will not mind if they have to keep the car for some time. Good thing is my warranty should cover software updates if they are effecting the car drivability.

 

@tkelley.EClass Any updates on your car?

 

MB has it now. Mercedes of Warwick RI is working with HQ to find a solution... more to come my friends...

 

Got the car back today. No solution. They said the new software js being finalized and will be ready the 1st week of January. So I'll have to come back then.

 

Thanks for sharing, I have same issue. Was this covered under warranty? I have a cpo warranty, but they charge a diagnostic fee if not covered by warranty and I do not authorize the repairs.

 

Mine is CPO and they did not charge me anything this time. The first time I dropped it off they charged me an hour of labor for the shift normalization.

 

Could you please share your dealership name and service advisor? I will provide this to my dealership and see if they can replicate