bladevanrusso

I have a US 2015 C300 7g 4matic. Had multiple resets and a transmission update, but no cigar. Dealer is now saying "works as designed". C'mon, even a Dogde Dart shifts multitudes better. Wondering if anyone out here that does NOT have that issue? And if so, what year and how many miles driven?

alyshehata

Same issue here on a 6,000 miles 2016 4MATIC. Rough shifts from 1st to 2nd and/or 2nd to 3rd. After that it is smooth as butter! I'm really trying to learn to live with it but every time I drive any other car I instantly feel bad about my car and the rough shifting. It's more apparent in S+ but surprisingly less apparent in S than in C or Eco. I'm taking it to the dealership this week to see if they can do anything about it but I am doubtful.

One thing I tried today is resetting the adaptation using the popular method posted here and then drivin it in S+ for a while. My hope is that the transmission adapts to the late shifts of S+ and in turn produces a smooth shift in C mode. It seems to have improved the jerks slightly but it is still there. I also noticed it tends to happen after the car warms up so not until the temp goes above 80 degrees. I really hope something can be done about it since that's my only issue with the car (and really, something that shouldn't be an issue in 2016...)

Mikey53

Mine seems to shift fine.

AAN

No shift problems whatsoever.

whippet007

Smooth as silk.

Have owned the C400 for 24 months and it has been an outstanding vehicle!

NYbenzzz

smooth shifting for me too.

however, i feel like the computer hesitates in choosing the right gear most of the time.

sometimes i'm just cruising down on local streets and the gear stays on like 2nd or 3rd with rpms into the 3k~4k wasting gas. i wish it can just maintain rpms into the 2Ks...

also, when flooring the gas pedal all the way, the transmition sometimes struggles to downshift and launch. has a slight hesitation, specially when trying to take over cars in the highway.

ManiacGT

It would be a useful diagnostic contribution for all those posting good or bad here, the exact model of their cars/engine/transmission .. the issues seem largely related to the 4 pot petrol with 7g+ tranny.

mine has this issue on a C200 with 7g+

Group 42

Mine sometimes is a bit harsh on upshifts in the lower gears but you can control it by easing back on the throttle a little, my main gripe is an occasional harsh downshift from 5th to 4th, worse when cold, dealer has looked at it and said it is OK, unfortunately you cannot balance the throttle on downshifts as it is usually off. there is a certain amount of self learning and adaptation to driving style with these transmissions so I am prepared to grin and bear it for a while as I haven't done many miles.

Cheers
Group 42

Mikey53

2016 C300 4 cyl 7 speed tran

bladevanrusso

Is there a way to start a poll here? Reading past threads, it seems a number of folks have this problem. The loaners I've driven have this too but at less pronounced levels. But hearing folks here say they don't have this 'feature' makes me want to call the dealer's bluff on 'works as designed'

Nope.
2015 C300 4matic
18k miles.
Been thru multiple TCU resets.
Have tried many driving strategies in attempts to make adaptation happy.
First 4 pot MB. Have a w212 e350. Traded a w204 6 cyl for a w205 c300. I'm disappointed

Webmoto

I had same issue but after dealer updated the transmission software approx 4 weeks ago all is good. Very smooth shifting. I've check the repair order but does not say from what version to what version was updated.
Also they did a ECU update and a ABS /brake update. On the repair order this is all is saying. No version number provided or other details.
2016 C300 4matic. 14k km.

bladevanrusso

Thanks, I'll ask. Did anyone else here have a recent TCU and ECU update?

This is the most frustrating car I've had.

Yeti575

1.6 Petrol. No jerks between 1-2, bad from 2-3, semi-bad from 3-4, smooth from 4-5 and up

beceen

C180 (euro version), 7-speed auto, no issues.
I had a software update done, though.

gfmohn

Could you please repeat the reset procedure? I've done it before, but I forget where I saw it. Others will profit from it too. I recently asked my dealer to do their best, and there was some improvement. It now shifts only a little roughly.

alyshehata

Sure. It's actually pretty simple. Get inside the car and make sure all windows are closed and turn off the COMAND or Audio 20 screen (just for safe measures). Next, push the keyless go button twice (if you don't have keyless go, turn your keys all the way to the right without turning the engine one). Next, push the gas pedal all the way down until you push the little button at the bottom. Leave your foot on the pedal for about 20 seconds, and you should hear a small whirring noise coming from the engine. While your foot is still on the gas pedal, press the keyless go button once to turn off everything (if you're using the key, turn it all the way to the left and keep the key in). Stay in the car for 2-5 minutes and do not touch anything. I've seen people say 2 minutes, but I noticed if I stay for 5 minutes, I hear an obvious clunk noise at the 4.5 minute mark that *may* indicate something is happening, so I would just recommend you stay for 5. Next open the door to make sure all electronics turn off, then turn on the car and drive.

I've noticed a GOOD improvement when adapting the transmission to Sport+. What I did was reset the adaptation like I described above, and drove for about 30 minutes on Sport+. Make sure you try and hit all gears a couple of times, so try to maybe drive it in a little bit of traffic so you end up speeding up, stopping, and slowing down, etc... Adapting it in Sport+ seems to have produced the best results. Still a little bit of jerk, but nothing like it was at first. When I get my car back from the dealership, if the issue is still there I will probably try to adapt using just Sport, and maybe another adaptation using Eco to compare the difference. I hope this is a good starting point for people here who are trying to fix this issue.

bladevanrusso

Yeah my beef with resetting adaptation is that its just a bandaid. Another month or so on the shifts will be just as harsh prior to reset and I'd be looking at redoing the process again. I lived with this for an entire year, each time experimenting with different driving strategies after reset. Plus the resets only "smoothens" out the harshness but not eliminate it.
Seriously this vehicle is more high maintenance than my girlfriend haha, and none of my cheaper vehicles in the past are anywhere near this touchy or clingy.

bladevanrusso

@alyshehata I need to try your Sports+ strategy! That's a permutation I haven't experimented with. Thanks!

Somewhat along the same or opposite lines, I installed a variable throttle controller called PotentBooster (similar to SprintBooster but with more granular tune options). Thought was to shorten shift points especially from 1-2 and trick/train adaptation. I was WOW'ed immediately afterI plugged that thing in and thought I finally came to a fix. But a few weeks later...onto another tranny reset.

alyshehata

Dealer told me a transmission update was being done on my car along with another fix (door handle bulbs went out) so I have a tiny bit of hope. Although it's very likely the update doesn't fix anything and i get told its part of the ''characteristics'' of the car.

I also noticed a slight vibration when braking when the car downshifts from 4 > 3. It's really not a major vibration but I can feel it in the brake pedal and the steering wheel. The loaner I have doesn't have this problem but still has very jerky shifts. Hoping to get my car back tomorrow and report any new findings

bladevanrusso

Good luck Aly and let us know. My last TCU update was in March. What that did was to shorten the shift point from 2 to 3 for unbeknownst reasons because all it did was to make that transition more abrupt, which pretty much just added more unrefinement to a car. Worst Mercedes, and honestly, any car I've ever owned.

skhan007

I was curious after reading this thread and went and tested out my car, paying particular attention to the shifting. I've only had the car a week, but had not noted any problems with shifting. Yesterday I drove it keeping a watchful eye and I noted a slight jump from second into third. This was only present when I was aggressively accelerating. I was in comfort mode and in sport plus mode and noted that aggressive acceleration resulted in a noticeable hop from 2nd to 3rd. However, the way I normally drive, I don't notice anything. As somebody else noted above, smooth as silk.

jlr82

How many of you have had W203s or W204s before getting a W205? Just curious because all W203's and W204's I've driven have had the shifting characteristics you guys are describing and it's just normal with these cars, unfortunately.

Resetting the TCU and adaptations is only temporary, it will always get back to not shifting the way you think it should. Or at least that's been my experience with W203s and W204s.

alyshehata

I actually had a w204 loaner a few days ago and it was smoother than anything I've ever driven. You absolutely cannot feel any shifts. It may be that it was higher mileage? (~20k) or it may be just a smoother transmission. The C300 I own definitely has a little jolt on the first 3 gears.

jlr82

My 2014 W204 has 21,000 and a few months after a TCU reset it shifts somewhat harshly through the first three gears as well. You'll find LOTS of W203/W204 threads about rough shifting. It's unfortunately very common and characteristic of the C-class setup. Even with the same transmission in the E-class it's characteristics are much different, and much smoother.

The W205 loaners I drove felt very much like my W204 in terms of the transmission characteristics and shift feeling, but maybe slightly smoother shifts, but depending on how you drive and adaptations, etc. it's slightly different on every MB.

GerritKw

I do not have the rough gear shifts as you describe.
My car is a C350e. It sometimes gives a tiny bump during downshifts but that is due to the recuperation.
No serious issues in my opinion.