Spearhead

I read these threads and see there are those who experience lots of jerks and thumps while others have very smooth shifting. Why, if we all have the same software, are we being told by Mercedes that it is only a software issue? Seems to me that the valve body and or TCU are defective on some cars, if not the transmissions itself. Blaming this on software only makes sense if all the 2015 C300s are shifting poorly. And yes, I have had my software updated to the latest version, with no improvement in the shifting.

MASSC450

What is your model, mileage, and what was the build date?

Xzer0

Is there a way to see what version firmware/update our C classes has?
How do you know if it needs an update?

Do they add features?
When is the next iOS update coming out? Oh yeah wrong kind of update
Anyway what do software updates do in the C class and how do you update it?

angeloxnet

not sure if the "jerks" are bad, i thought it was the rev matching.
similar to the S4 I test drove when i down shifted it did something similar.

ManiacGT

My D2 to D3 change is bad until say after 10 miles or so when the car is warmed up. Most of my journeys are circa 5 miles and D2 to D3 shifts 'catch' badly to the point it feels like someone dabbed the brakes while shifting making you move in your seat. It seems others at least with the same 4cyl petrol engine and 7G auto have similar issues. It feels to me like there is some mismatch between engine revs vs gearbox revs. Sometimes a little over revving sometimes under revving. It can't be good for the powertrain.

whippet007

My C-400 4matic shifts perfectly in every mode.

megaoctane

I believe @vic viper said the problem is mostly limited to the small petrol engines (C180, C200), the M274 engine.
I have the same issue with my C180.

ManiacGT

Indeed, as mentioned in my post and Vic's it seems related to petrol 4 pot's. I would assume software is possibly different for each engine/transmission pairing and therefore if it is software its likely only that which relates to the 4 pot petrol.

digitallust_aus

My C250 Bluetec also shifts smoothly and perfectly every time.
March 2015 Build, 2,700km ☺

ManiacGT

I'm sure no one is taking note of the twice I've said 4 pot petrols ONLY appear to have this issue to date.

digitallust_aus

Settle down sunshine sheesh... Diesel / Petrol... The gearboxes are physically the same.

ManiacGT

But the engine and associated programming is not. Sweetheart.

Spearhead

Is the Mercedes across the pond that you call C250 the equivalent to the C300 here in the colonies?

juwivive

The UK C250 is a diesel (Bluetec). Other than the C63/C63S and the C200, we Brits don't have any petrol/gasoline models to choose from. This is in contrast to the rest of the Europe (even the Republic of Ireland, which also drives on the left), where they get higher powered petrol variants.

W205

This is sadly not only related to the petrol cars . Our c250 Bluetec also has this problem. the downshift from 3rd to 2nd is really bad when the transmission/engine is cold, even 5th to 4th is kinda jerky. its as you say, feels like someone is dabbing the brakes for a split second.

ManiacGT

Then I take my assertions back although this is the first diesel to be reporting this.

The issue for me is upshifting, D2>D3 mainly. Downshifts seem fine.

digitallust_aus

Downunder, we only have C200/C250 Petrol and C200/C250 Bluetec Diesel.
The C250 in both variants is range topping with nearly every option thrown at it.
The C300 in Australia is only in a Bluetec Hybrid Version..
Essentially a C250 (same engine and equipment specs) with the addition of a small hybrid set up is identical to a C250 Bluetec........ with a $4,000 price hike.

I am not sure if MB will follow BMW's path in Australia back in 2013
When I bought my BMW F30 320d there was only
a 320i/d 328i and 335i... about 12 months after the Aus launch they sent over the 316i and 318d

digitallust_aus

I originally had you pegged as princess, but backtracked on that one

PeterUbers

It's an issue in all Benz models guys

See my links in this thread

https://mbworld.org/forums/w212-amg/...lemon-law.html

turt

Apparently my C 180 petrol is fine, but it's a recent build so maybe they fixed it for new cars?

Jadis

Wow I just read both of your 7 page sagas. Seems to me that plain and simple the MB 7G transmission these cars use just plain isn't very good.


From your description of the symptoms the bad shifts felt extremely bad, like being hit from behind.


On my C300 I would characterize a "bad" shift as "a slight but noticeable" jerk. Nowhere near "neck or body jerking" or "like being rear ended". For me it seems to happen on a downshift from 3-2, but also on harder acceleration from 2->3 and 3->4. But again, not all the time and I am not sure it's worth putting in the car for service. At least not yet.

ManiacGT

I was going for gorgeous but as I've never met you..

digitallust_aus

Hahahaha

vic viper

According to the info I have the upshift 2-3 problem is only related to the M274 Engine, commersially named C180, C200, C250, C300 and also the C350 plug in hybrid.

ManiacGT

Vic, as you're on the inside, can I ask, are you aware of any fix for this as yet, software update or mechanical? If so, I'm going to get the car booked in to the dealer as not only is this uncomfortable, I'm concerned about wear on the transmission/drive train.