Cosworth2000

Hello All,

Well after looking all over the internet to see if any others have had problems with their 2016 C450 AMG vehicle's transmission, I decided to make a post so that it would SEO.

I am aware that there are some post around for the W205 C300 and the C400 having transmission related issues pertaining to Gear 2 and Gear 3 whereas it would seem that the transmission is having problems by either engaging improperly, slipping or shakes the car back and forth on gear changes.

My W205 / C450 AMG comes with the 7G Plus Transmission built by Mercedes-AMG. It just hit 1200km but the issue started before that. In or around 500-700km or so the problem started whereas it felt like the transmission was harshly engaging gear 2 to gear 3. I drive a lost so the car was about a week old and came with just 12km on it from the dealership.

Needless to say, this issue seems to come and go however on our first day of real heat here in Toronto, the car really showed it's downside. On gear changes from 2-3 it would feel harsh and shake the car badly. Please realize that the car has only been in either Comfort or ECO mode when it would do this. If you put the car into Sport or Sport +, it would not feel like this issue exist however it was not a smooth gear change.

Some background.

The car was purchased at Brampton Mercedes on April 5th, 2016.

I took the car to Thornhill Mercedes on April 15th and it was returned to me on April 16, 2016 with a new flash and some additional features.

It would seem that the problem was resolved however I did not want to believe that the problem was still there, so I kept driving so that I could break-in the engine.

Well on April 19th, 2016 - the car seemed to be going through the same issues however since I could see what was really going on pertain to the gears in the AMG setting, I paid attention to the engine oil and transmission oil temperature which was helpful.

This is what I noticed.

While the car is in Comfort Mode, it starts in 2nd Gear, the engine would reach 1000 RPM, then fall to 900RPM (or so) and then got back up to 1000RPM, then it would switch to 3rd gear.

At this time the temperature of the transmission was 73 degrees.

I was near Downtown Mercedes and a tech took the car for a ride to see if he could find out what the problem was. He stated that he was not sure what the problem was however he did noticed that it could possible by a torque converter issue or a transmission solenoid issue issue since it looked like the transmission was trying to shift gears early but he could figure out the exact problem. He stated that he has never seen any issues like this before with the C450 AMG, especially the 2016 model build range model.

He stated that he would need to pull the transmission data and send it to some engineer in MB somewhere...this is still on going but has not been done as of yet.

Fact:
1. Transmission slips or wants to change gears at 1000RPM however that is not a gear change interval.
2. This problem only happens once the transmission oil gets to 60-73 degrees Celsius.
3. It always slips or skips or whatever at 1000 RPM and not in any other gear except gear 2.

As of Today - April 21, 2016 = the problem has not been resolved.

Has anyone else had this problem?

The car will be going back to Thorn Hill Mercedes since I live up that way.

Funkwagen

Sounds like faulty/poorly timed engagement of the torque converter lockup clutch to me. Take a look at page 16 of this document, I believe it has something to do with this. Although this is an older document for the 7g-Tronic non-plus, I'm pretty sure the function is the same. (w204 only experience from here, but also using the 7g-tronic transmission..) This was a problem for me when I had a vacuum leak from the brake booster resulting in a loss of some engine power and it felt like the transmission was engaging the lockup clutch too soon for the engine to gain enough power/torque for it to be a smooth transition. I think it's the result of some miscommunication between the engine ECU and the transmission ECU; the transmission thinks it's getting a certain amount of power/torque at 1000rpm, when in reality it isn't.

Since fixing the vacuum leak, I've not had this problem again in C or S mode. I'm not saying you have a vacuum leak, however. It could be anything, but I think the problem stems from this. I could be wrong, though, since I'm not sure what revisions have been made to the 7g-tronic+ in the w205 models

deezeldude

I hope they figure this out! I am only beginning to test the limit of my C450 now that I hit 1500. But no, these issues I have not detected in my car. I will monitor a little closer now.
Thanks for the post and GOOD LUCK!

chango450

Sorry to hear about your issues. Luckily I have yet to encounter this problem (knock on wood). I bought my car through Thornhill Mercedes. Pretty much drive it like I stole it from day 1- I've logged on around 2800km.

If the problem persists, maybe you should bring it up with Mercedes Canada and see if they can resolve your issue- a new car perhaps.

Cosworth2000

Thanks guys.. I hope to have some details later next week since they don't think that they will be able to fix the transmission today (Friday April 22, 2016).

On another note the 7G Plus is dual clutch transmission and not a single clutch tranny that is used in the 7G as the Plus belongs to the AMG model of vehicle according to the AMG site.

I will allow the dealership to work on the problem first however if the vehicle needs the new transmission it should be expedited and I should not have to wait a month or more to get a tranny replacement.

Cosworth2000

April 28, 2016

Mercedes C450 AMG Transmission issue unresolved by Mercedes Benz https://youtu.be/VUjBOVCb14o2016

So I got a call to pick up my car stating that AMG Transmission looked over the program for the transmission and they updated it again and everything was to work fine. So yesterday I picked up the car and drop it home. It did not reach 60 degree as MB Thornhill is closed to my house.

This morning on my normal drive to work, I get close to the highway and I feel something but at that point I'm already onto the 401 hwy.

I get off the hwy like I normally do and stop at the lights. Light turns green and while still in Comfort mode, the car jerks like it did previously did, as per my issue. The transmission temperature was at 73 degrees. It was slipping or jerking at 1000 RPM and in 2nd gear without changing to 3rd gear. I messaged Thornhill and I'm told that their foreman did not drive my car or did not know how to tell AMG what the problem was . . . . really... do you guys understand what I'm saying.

"My C450 AMG Transmission slips in 2nd gear - acts like its changing gears but there is no gear change. It does this between 60-75 degree Celsius. "

I'm speaking English here? Well the car has to go back to MB however they still feel that there is nothing mechanically wrong with my transmission with just now 1500km on it. The car is not even 1 month old but this is becoming ridiculous and I want others to know how this matter has not been resolved and has been going around and around in a circle.

Cosworth2000

Well, got my C450 AMG back.. Funny...still the same problem. I'm pissed as my in-car camera caught the mechanics speeding all over the place. Guy gets into my car and states "oh, the car has over 360hp". What? MB Mechanic does not know how the C450 is built? He takes my vehicle up to 115km on Hwy 7, then slams on the breaks at one point so the red light camera would not catch him. He then speeds through traffic, zooming in and out. I told them my transmission slips in 2nd gear. How does he expect to see what is going on when he is racing around the streets. So now, they are coming to bring me a loaner again and this time I need to sit down with the foreman and walk him through the issue. They drove my car around 2x, had the hood up, washed the car and told me it was okay. Poor service since I have bought this vehicle and it's only getting worse. I have had better service while owning a Mazda than a Benz and this should not be. What upsets me the most is that my car had not even reach the break-in point and this guy was racing my vehicle when I never did that since I bought it. Yeah, you know I'm not going to stop there as I have LIVE footage of his abuse to my vehicle.

jester4

I'm curious to hear what they have to say

Mr. J

I think you need to have a sit down with the GM. Show him the footage explain the situation, and then ASK him what he intends to do to make it right. Keep calm and give him an opportunity correct this. If he blows you off (very unlikely) escalate it to MB Corporate.

Mike5215

I'm not sure it rises to the level of "abuse" necessarily. It's a performance car and all that. I guess they could argue they were getting it up to temp. More importantly, have you been able to take a tech out in the car and replicate the issue?

That seems like the next step, and ask for your service team's Lead Tech for the ride along. The few times I've had an issue they couldn't duplicate, the lead tech ride-along did the trick. Surprised the tranny control unit isn't throwing fault codes.

Webmoto

You might also want to have this issue checked by a different dealer from GTA....

J2016 E63

Just sent my 2016 E63 back in (again) for the same transmission issues

aimless

Alright. I want you guys to try something. I think I found a way to replicate the slipping you are taking about.

Set the car to manual in individual settings. The rest doesn't matter.

At a full stop shift into 2nd gear. The car will now start in 2nd and will not downshift into 1st when coming to a stop.

Now take off at 25-30% throttle.

For me, the car will rev up, start moving, once it hits 1500 rpm it will drop about 200rpm and then continue upwards.

I'm pretty sure that's what you are talking about and it is really pronounced in manual mode.

I took a video of it so if you no one can replicate I'll upload it. But it happens every single time without fail.

Webmoto

Any update? Is the issue fixed?

meto

Hi all
I've 2016 C180 with the same problem, harsh transmission shift between 2nd and 3rd gear shifts and sometimes between 1st and 2nd gear shifts.
I've reported the issue starting almost 1000 km odometer, took my car to the delear who has confirmed that this isn't normal and we will check your issue
1- they performed software update and the problem exists.
2- they have changed the body valve and no help.
3- they have completely changed the transmission with a brand new one and the problem still exists.
finally they told me this is the characteristic of your car and all cars in this model are the same as per the manufacturer's feedback.
I don't know what actually should I do?
any help?

jimmycrackcorn

[QUOTE=Cosworth2000;6779094]Hello All, I used to own a 2016 C450 AMG. I purchased it in October 2015 and was able to drive it with no transmission problems until I reached 5,500 miles on the odometer. I would have same thump/hard shifting feeling in gear 2 in C or E mode or in gear 1 in sport+ mode before up shift to next gear. It always happened between 8-12 miles Mph. I took it in to dealer and they flashed or reprogramed the transmission and the problem still exist. I took it back and they put in a new solenoid and the program still existed. I took it back a third time and the changed out the torque converter and the problem was still there. I had multiplayer drives with 2 foremans to confirm problem and they agreed it still needed to be worked on. After 3 attempts to fix transmission and 10 months of having to get multiple car loaners, at on time up to a month with out my car totally maybe 16 weeks of not having my car I called Mbusa to initiate the Car Buy Back program/Lemon Law. It took about 3-4 weeks to get everything taken care of. I surrender the car last week and they wrote me a check for all my car payments from the time I had transmission issues till the time I surrender the car. About 5 days later they payed off the remaining car loan that I had with credit union. I really loved this car minus the transmission problems, I am looking for another new one right now with options close to what I had. I'll never find another one fully loaded again with black obsidian paint job because the inventory for them is getting slim. Just thought I give you my experience. Good luck to all with similar issues. Jimmy

matoo

i just got my 450 back from the dealer been there about a month for the same issue they replaced the whole trans and other parts shifts smooth as butter now but i believe after they replaced the parts they said something about the car not sending enough trans fluid through which was causing these issues

tivoboy

I just started having an issue the other day with mine.. 4600 miles now.

In S+, after driving a while, from a start just starting normally no RACE start or anything the car will jerk and pause and jerk and pause lunge and stop lunge and stop..only switching it out of S+ stops this from happening.

anyone seen that sort of thing?

tezro

@tivoboy

It sounds like I have the same problem as you. 1000 miles and it initially feels like it is having a problem in S+ mode. I would guess between gears 2-3, especially when shifting down.

tivoboy

Sounds like after break in. I would reset the transmission going forward. I did that at 1500 miles after the break in period.

tezro

I will give this a try and let you know.

c_sotelo5

I had a similar issue on my c450 at 3000 miles. I had a broken retaining spring which caused the "k2" solenoid to fall out of a sealed socket. My cap wouldnt move at all. Luckily this happened on a low speed zone.

JBMCL

How do you reset it?

Chris Braun

Honestly I have heard many people complain about the same transmission problem and every dealer ship seems to say the same thing: nothing is mechanically wrong with it. I think since the new 9g tronic transmission is new people aren't used to it yet but considering the fact that all of these dealers can't find anything wrong with it and say that there are no mechanical problems with it, and it's happening to so many cars at such low mileage, I think it's just a characteristic of the car. A quirk.

inhartwetrust

450s have the 7 speed.