blizzard12

Dear highly praised German engineers,
Your 7G transmission is GARBAGE!

Beside all the shifting issues now this:

MariTheBoss

I don't understand your video

JAMADOR

^ I'll 2nd that. I'd expect it to shift under the extremely light acceleration demonstrated in the video above.
In the month I've had my C300, the only thing with the trans I've noticed is some slightly jerky shifting at low speeds in Comfort between 1st-3rd, seems like it's trying to get into higher gears a little too soon. Not as pronounced in Eco, S or S+.
I have I set to full manual, so no problem there either.

blizzard12

One would expect the transmission to shift at higher rpm in sport mode, let alone in sport plus. Yet this tranamission shifts up at the same low rpm in sport+ as in comfort mode.
As you can see in the video the transmission is in S+ and it shifts up at <2.000 rpm. Well, that's not exaclty what "sport" means...

JAMADOR

It also looks like you're barely on the throttle, so I'd expect it to upshift as exhibited. It took 19 seconds to go from 25-50 kmh, so that's pretty lethargic acceleration.
With a bit more throttle input, it definitely holds gears longer & doesn't race it's way into 7th like it does in E & C.

GerritKw

I do not know how long you have driven this car, but when you would have stepped a bit more on the . accelerator you would have known that the gears also switched at higher rpm.

blizzard12

I understand what you mean, but then why have Dynamic Select? Why not just let this "super smart" transmission shift based on your acceleration pattern?

...and here's more inconsistencies with this transmission, and this is what I hate the most about it:

blizzard12

One super annoying thing is 2nd gear: it revs up to 3.000+ rpm in 1st and it shifts into second. The harder I accelerate in 2nd the shorter it makes the 2nd gear before it shifts into 3rd.
I can literally make the 2nd only a fraction of a second by accelerating hard enough right after it shifted from 1st to 2nd. How stupid is that? Actually that is just as stupid as it was programmed.
Hey you German engineers! Your transmission is GARBAGE!

blizzard12

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fabbrisd1

Frankly - the 7G is a reliable work horse - of course the 9G match in the W205 is next level forward.

I might suggest that you take some time to build experience with your Paddles - using both "single click" technique - and 2.5 sec "pull and hold" technique - if you want to enjoy your driving more - that's one direction you can take to build more experience with your MB....

If you want to give MB Engineers more input - get a large white paper sheet - newspaper size - take a magic marker and draw a outline of your right foot - send it to FFMOC (Fat Foot Mercedes Owners Club) Stuttgart Germany ... and the club will make sure the "Mercedes Engineers" get it..

blizzard12

Thanks for your response.
It might be reliable, I never questioned its durability, but there is definately a major issue with its software. As for "reliability" I know for sure I can't rely on it to shift in time from 1st to 2nd unless I do some magic with my foot on the pedal.

Tried that. Paddle shifting is not exacty comfortable when the steering wheel is at an angle > 45°, like in a 90° turn/cornering. Actually you kind of have to twist your arm...
Also, it has happened that the transmission automatically downshifted at the same time as me doing it manually resulting in bad a jerk (as it downshifted 2 gears in one shot). I know this happened because the engine was getting close to the lowest rpm for that gear, but it wasn't a nice feeling.
BTW, never did the 2.5 second "pull and hold". What does it do?

Mmmmm, can you please explain in more detail?

Thanks

ezshift5

'Fab, is that a tongue in your cheek?


sign me appreciative.




ez

JAMADOR

Also, if it continues to be an issue, you could talk to the dealer & maybe have them reflash the trans, maybe a software update or refresh could help?

I did notice that mine does tend to short shift 2nd into 3rd with light throttle application.

blizzard12

Thanks for your reply.
It has been an issue since the car was new, almost 2 years ago.
The car has been back to the dealership for software update and transmission adaptation so manny times that the dealership told me if I kept going back with the same issue they would start charging me. They said that the last adaptation is the best they could do. Period. And I say: it's still crap!

nick_wass

chicago-guy

In S+, my C300 holds D2 up to 3100 RPM, which is usually around 25 MPH or so. It will hold at that indefinitely unless I briefly speed up to 27 MPH or so or upshift manually. I have a somewhat early build date (4/2015) and I have read in other threads in this forum that certain changes were made to the C300's performance mid-2015 to make it a bit less sporty, possibly to encourage sales of the pricier but less-popular C400. One of those was removal of a burble or "cough" when shifting between gears (in S+ only), a sound more typically heard in sports cars. I wonder if another change at this time, and for the same reason, might have been taming the transmission a bit. Or that change could genuinely have been an attempt to improve S+ fuel economy, because my average is barely 18 MPG now that I drive in S+ exclusively. (I find the engine sluggish and the transmission hesitant in any other mode.) I would not get another model with the 7G, and I'd want to test drive the 9G very thoroughly before buying.

blizzard12

Yeah, pretty much all the C300 loaners and demos I have driven exhibited the same behavior.
Just how much does it bother you? I for one, am going nuts that I always have to cheer for a proper 1-2-3 shifting and of course it almost never happens.

blizzard12

Having to combine auto with manual shifting is super annoying and distracting. Can't enjoy driving as I always have to keep an eye on the tachometer.
Also, driving in S or S+ is not really the fix I am looking for for the shifting issues. Besides, if I'm gentle on the acceleration even S or S+ will "adapt" and eventually act just like confort mode as seen in the video above.

Cali4niadriver

Cali4niadriver

chicago-guy

That's disappointing to hear.

Cali4niadriver

gfmohn

A spectre is haunting Mercedes non-AMG C-class owners - the spectre of "family sedan." In the US, German cars are exotic imports, loved by owners who love driving. I am writing this from Germany, where a majority of the MBs, BMWs, and Audis are estates (station wagons). On the autobahns, these "sport sedans" are pulling trailers just as often as lesser cars. Very few are driving over 120kps (75mph), even where speed is unlimited. I have been driving in Germany several weeks a year for 19 years. In previous years, I pretty much drove as at home in the US (in the Northeast).

This year, I have driven from Leipzig in the East to not far from the Danish border in the North. Everywhere, I have found that German drivers are driving much slower. Within all town and city borders, the speed limit is 50kps (31mph). This includes long stretches of wide-open parkways, straight, wide roads leading out of town, etc. In the past, German drivers would have been driving these roads at 40-45mph. Now, the combination of increasing numbers of speed cameras and a real belief in saving the environment has German drivers religiously observing the speed limits.

This is the market for which Mercedes engineers are designing their cars. The first priority MB transmissions is saving fuel. I would say that the second is smooth operation under light acceleration, except for the jerkiness of the upshifts and downshifts between 2nd and 3rd. So just say "family sedan" to yourselves three times and start saving for an AMG.

blizzard12

I would really like to see some scientific evidence as to HOW a transmisaion saves fuel by letting the engine roar at 3.500 RPM in 1st gear under normal/light acceleration!

If revving the engine high is so fuel efficient then why does the 9G transmission not do the same? Why none of the other brands do the same? BMW, Audi, Volvo, anyone?

As stated in the video: I don't buy the "fuel saving" B.S.
I personally believe the "fuel efficiency" explanation is just a lie concocted by the manufacturer for not wanting or being unable to fix the issues with their 7G transmission.
​​​​​​​Unfortunately most people don't know much about internal combustion engines, torque converters and transmissions and they fall for any "explanation" they are given. Actually most of them don't even care about RPM and shifting as long as they can get from A to B in a high end car.

skim7x

I think you're like me and want to be in full control of the transmission -- you don't want the transmission deciding for you when to switch gears. Which is why I love manuals... To Too this car didn't come with stick otherwise I would have gotten that option.

In the meantime, you just have to accept that no automatic transmission is going to read your mind and shift exactly when you want it to all of the time. I have to say the c63 transmission software is very good. In Sport+, it doesn't shift until very high revs no matter how light you are on the throttle. That said, sometimes that's not even what I want so I just go to manual mode so that I can be in full control -- usually when I want the responsiveness of Sport+ but don't want to be cruising at 6500rpm haha.