Anotherone

Was driving the other day in Sport mode and the car bucked real hard as if I had hit a pot hole when going from 2nd to 3rd gear. I was light on the throttle and let go of the gas when cars are braking, but as soon as I gave it gas and it shifted and bucked. Drives fine and I didn't smell anything afterwards - I know the MCT has some issues but never have I experienced anything like that.

Astolfo

I am taking my brand new 2016 for the same issue crazy bad, does it feel like as if the tooth did not align or the car bucked?

PeterUbers

ive had this happen when coming to a slow roll from cruising speed to about 5mph then jumped on the gas... 2nd to 1st ... then throttle and mct re engaged into first ... bucked hard ...also in s or s+ mode

never had the scenario you had ... how many miles on the car and how has it driven otherwise?

Anotherone

Something like that - very bad jolt. What dealer are you going to? I emailed my SA at Lynnwood and he told me to bring it in, he hasn't had anyone come in with the issue.

I'm going to wait because it drives fine, but I had concerns about the 4Matic/Diff had malfunctioned.

Anotherone

8500 miles currently. It drives fine, I drive mostly in Sport + mode and never had issues in that mode. Now I stick to Comfort or Sport+, Sport takes too long to find a gear.

Astolfo

Bellevue, I let you know I am going at about 130.
Let me know how you get treated

Anotherone

Sounds good! There is only one person I trust at Bellevue, believe his name is Ken or Marc. He is the other gentlemen when you enter the service bay on the left.

Lynnwood has treated me great - went there for the diff service and my service A.

PeterUbers

naperville benz

benz won't find anything on your car but worth taking in for peace of mind

readapt in S mode and you may like it better

Astolfo

I just went for a drive, I reproduced the problem the tech acknowledged it! he has a fix, so he says; a cold-warm-hot adaptation and to do it properly it need 2-3 days It measures the gaps in all gear possible combinations and adjusts. He says it will shift a lot smoother than what it is shifting most of the time now. Which to me, it would be as awesome as a 2016 PDK.
How cool that will be. I need to make an appointment now...

PeterUbers

dont get too excited this is a custom adaptation and the tech will take your car everywhere and to his house in the evening

i had this done on my e550's and it didn't work

im optimistic for you .. the tech can identify which shift points are at the outlying adaptation acceptable range and modify these values but they can change again

no one can make this mct ever come close to 2016 pdk, but we can sure dream and I won't get in your way of that

CarHopper

I'm willing to bet you guys are just experiencing this in a "sweet spot" if you will. If it doesn't happen every single downshift I wouldn't worry all too much. I can see a scenario where you are catching the car mid process (shifting, applying power, whatever) and this happens.

Example, you're coasting in 3rd up to a red light allowing the car to slow itself. Light turns green and you press the gas at the same time the car is making the decision to shift from 3rd to 2nd. You're going to get some funkiness in there and I'm willing to bet that's the bucking you felt.

Being in S+ cruising around will lead to this. Most aggressive setting so you're going to get more aggressive, or faster, behavior out of the car.

I experienced similar behavior in both my c63 and my e63. My solution has been to stick with either C or M driving modes. At least in M there are no real shift surprises and if I get lazy or forget to downshift the car is still pretty smooth about it anyway. The only time S+ is used for me is when using the race start feature.

Astolfo

this could be...but I expect better, I drive other spaghetti and kraut cars (like the advisor told me) and I do not experience this issue. The only thing I am after is quicker shifts as regardless the mode I usually find myself shifting, specially when braking in

CarHopper

4500lb car that can get you from 0-60 in the neighborhood of 3.5 seconds while giving you a heated massage and put a smile on 4 of your friends faces at the same time with a trunk full of beach gear/luggage/bodies/whatever.. At the end of the day, for the price, you could actually say the car exceeds expectations depending on perspective.

I do hear where you are coming from though where you'd expect things to be completely buttoned up in a $100k+ car. That said, I bet you could get a Maybach to buck and that car is solely designed for comfort.

I bet someday the technology / processing power is there so that the car can make the decisions even quicker thus eliminating the buck. In the meantime, I'm okay with a buck/bog every once in a while which as I said I seldom come across because I'm usually in C or M. I get it in M when I don't downshift and the car does it for itself AND I'm right in the middle of going from decelerating to accelerating.

Bottom line -- I wouldn't worry too much about it if I were you guys. Going to the dealer may bring the peace of mind or do the opposite if they can't recreate the problem. At the end of the day, taking your car to the dealer just ensures that a tech has himself a good time in your car and then comes back and shrugs his shoulders or tells you to go have your car adapt to your driving style when it comes to this issue.

Just my 2 cents

izzy63

mine also has harsh shift from 2-3rd gear let me know if ur issue gets resolved

CarHopper

Afterthought - I was referring to downshifts and notice now that people are talking about upshifting issues. Just wanted to put that out there.

Astolfo

A couple of things at $138K is a lot of $ for a car. Yes it does bring a smile every day I go to work, at the same time I expect things to work. there is no reason for such a huge bucking and I truly fear it will break something. it feels like hitting a perfect sized pothole.


If it can be fixed why not? because the mechanic is going to take it home?
Bu I believe that people (until I am proven wrong) do things in good will. but I will have my logging on
If the dealer takes it for a long ride I will know and make sure I report it.

CarHopper

^ Oh absolutely, I misread at first as well and thought that this was a downshifting issue. On the upshift the car has had plenty of time to figure out what's coming.

That's why I made my afterthought post.

Anotherone

Probably going to wait and see if something else happens - don't want to waste their time or mine.

In Sport+ the car doesn't give me any issues at all - in upshifts or downshifts, only Sport mode is where I get the bucking from 2nd to 3rd upshifts.

CarHopper

Every single time?

Stereolab42

For me it's about 50% of the time when coming from a dead stop in sport mode, car will buck back and forth somewhere within the ramp to 20 mph. I either have to back off and feather or go all-out (and I can rarely go all-out in THIS car in any populated area).

TTMerc

Mine does it as well. Feels like something loose though Trans mount or motor mount

Astolfo

Taking my car on Tuesday, I should have it by Wednesday I hope. I was talking to another tech and we went for a ride. He also said that car is 3 updates behind and that the adaptation usually gets done in before the QA and after if needed; but mine shows none, and that the adaptation should resolve the bucking, and that the car will shift with more smoothly with with the latest code.
I do not want to get my hopes up but I am optimistic...
The one thing is that I really like is how the CCB breaks feel, not much travel and extremely linear.

Astolfo

Got my car back today after an adaptation being done.


In 30 miles of hard shifting back and forth it slightly bucked once. In the past I could make it buck hard almost at will.


I was told to take it and see how it feels, as they have not had time to do the warm cold. usually the adaptation goes cold, war, hot. Then let the transmission cool down, bring it up to "hot", and do hot to warm and war to cold.


I will get the car back to them in a couple of weeks to replace the camera control unit and the compartments under seats.


Good interaction with the service department so far.

Elchin Lat

Hello. Have you managed to fix the issue? if yes, what was the issue? My W205 is doing same currenyly. Thanks

brfatal

TCU tune resolved this for me. But given we don't have the same car, how are all of your mounts looking?