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I know there are other threads on transmission issues but I figured I would share my experience that I didn't see mentioned in other threads.
I took in my C400 last week for a broken wiper, brake peddle noises (air hiss and squeaking), and transmission issues that most have experienced.
When coming to stop and the car starts to downshift from 4-3 and 3-2, there is a noticeable jerk, like someone slamming on the brakes almost. Upshifts from 2-3 are shorter and also jerks. I usually drive in Comfort mode but I have felt the downshifts in S and S+ even worse. Feels like I'm gonna give myself whiplash.
My service manager updated me today and they think it's the clutch packs that are bad. They have already gotten some sort of approval from MB to start working on it. The clutch packs are ordered and they'll be tearing down the transmission this week. They'll be doing more testing after the clutch pack replacement. I'll update if this solves the issue since it may help others.
Hi. I found your post while i was searching for Transmission Problem. Has your car been fixed? Is this common problem with the 9-G gear box?
I have the same problem with my 2017 C43 which i believe the internals are the same as C450. The car jerks when shifting between 3-2 as similar to your description. The dealer here (Thailand) is still working with MB to diagnose and pinpoint the issue. I don't drive it hard very often and mostly use Comfort Mode considering the traffic here in Bangkok. The car is 2 months old and it's pretty heart-breaking that the car has been with the dealer for 2 weeks now. They still don't know what's happening and waiting for MB for further action.
Anyway, hope your car is fixed and on the road soon.
Hi. I found your post while i was searching for Transmission Problem. Has your car been fixed? Is this common problem with the 9-G gear box?
I have the same problem with my 2017 C43 which i believe the internals are the same as C450. The car jerks when shifting between 3-2 as similar to your description. The dealer here (Thailand) is still working with MB to diagnose and pinpoint the issue. I don't drive it hard very often and mostly use Comfort Mode considering the traffic here in Bangkok. The car is 2 months old and it's pretty heart-breaking that the car has been with the dealer for 2 weeks now. They still don't know what's happening and waiting for MB for further action.
Anyway, hope your car is fixed and on the road soon.
Unfortunately, I can't say for sure that it will apply for the C43 or C450. The C400 has the 7-G transmission and my car is still at the dealer. The dealer said they would be done sometime this week if not the beginning of next week.
I believe others on here have had some luck by having Mercedes update the software. You can try asking some of the guys over in the C43 forum. Here's a thread I found.
Unfortunately, I can't say for sure that it will apply for the C43 or C450. The C400 has the 7-G transmission and my car is still at the dealer. The dealer said they would be done sometime this week if not the beginning of next week.
I believe others on here have had some luck by having Mercedes update the software. You can try asking some of the guys over in the C43 forum. Here's a thread I found.
Finally got my car back. Shout out to Mercedes-Benz of Sugar Land here is Texas. They were very helpful and updated me frequently letting me know what was going on.
In my original post I said that they would replace the clutch packs but after an update form the dealer, they ended up replacing the transmission valve body. Car shifts so smoothly now. When coming to stop, there is no more jerking when the car downshifts from 4-3 or 3-2. upshifting feels smoother now as well.
For those with the 7G transmission having similar issues I described and the dealer couldn't figure out what was wrong trying mentioning the transmission valve body to them! I hope this helps!
Finally got my car back. Shout out to Mercedes-Benz of Sugar Land here is Texas. They were very helpful and updated me frequently letting me know what was going on.
In my original post I said that they would replace the clutch packs but after an update form the dealer, they ended up replacing the transmission valve body. Car shifts so smoothly now. When coming to stop, there is no more jerking when the car downshifts from 4-3 or 3-2. upshifting feels smoother now as well.
For those with the 7G transmission having similar issues I described and the dealer couldn't figure out what was wrong trying mentioning the transmission valve body to them! I hope this helps!
Good to know, thank you! So far my C400 transmission has been very smooth but if that ever changes this is very good info.
Finally got my car back. Shout out to Mercedes-Benz of Sugar Land here is Texas. They were very helpful and updated me frequently letting me know what was going on.
In my original post I said that they would replace the clutch packs but after an update form the dealer, they ended up replacing the transmission valve body. Car shifts so smoothly now. When coming to stop, there is no more jerking when the car downshifts from 4-3 or 3-2. upshifting feels smoother now as well.
For those with the 7G transmission having similar issues I described and the dealer couldn't figure out what was wrong trying mentioning the transmission valve body to them! I hope this helps!
Hmm my dealer has been saying that it's normal and that's how they are as far as the jerkiness goes... It's gotten better after a software update but i still feel it every day.. Do you think you can post the part number on here from your receipt? If the price is not bad, i might just pay out of pocket and swap it out rather than going back and forth with the dealer wasting my time.. thanks in advance!
Hmm my dealer has been saying that it's normal and that's how they are as far as the jerkiness goes... It's gotten better after a software update but i still feel it every day.. Do you think you can post the part number on here from your receipt? If the price is not bad, i might just pay out of pocket and swap it out rather than going back and forth with the dealer wasting my time.. thanks in advance!
I would like to see the service paperwork or part number as well. I am having the same issues.
Hmm my dealer has been saying that it's normal and that's how they are as far as the jerkiness goes... It's gotten better after a software update but i still feel it every day.. Do you think you can post the part number on here from your receipt? If the price is not bad, i might just pay out of pocket and swap it out rather than going back and forth with the dealer wasting my time.. thanks in advance!
Originally Posted by C400Benzeno
I would like to see the service paperwork or part number as well. I am having the same issues.
I'll post the service paperwork when I get a chance tonight. On another note it's been about 2 months since the service was done. The transmission feels much better when downshifting in comfort mode. On the first day I did not feel any jerking, after a week though, I slightly felt some but as richysh said and some others that I have read, it is normal and expected. The jerking I felt before though was very excessive and felt like someone stomped on the brakes. When coming to a stop or slowing down now the jerking is usually not noticeable and if it is it isn't neck jerking whiplash like before lol.
I know there are other threads on transmission issues but I figured I would share my experience that I didn't see mentioned in other threads.
I took in my C400 last week for a broken wiper, brake peddle noises (air hiss and squeaking), and transmission issues that most have experienced.
When coming to stop and the car starts to downshift from 4-3 and 3-2, there is a noticeable jerk, like someone slamming on the brakes almost. Upshifts from 2-3 are shorter and also jerks. I usually drive in Comfort mode but I have felt the downshifts in S and S+ even worse. Feels like I'm gonna give myself whiplash.
My service manager updated me today and they think it's the clutch packs that are bad. They have already gotten some sort of approval from MB to start working on it. The clutch packs are ordered and they'll be tearing down the transmission this week. They'll be doing more testing after the clutch pack replacement. I'll update if this solves the issue since it may help others.
hi there I bought a used 2015 few weeks ago and I have taken it to dealer 2 weeks out of the 3 that I had it
rear side sagging, so they replaced the air shocks and caliberated it like 5 times so I will monitor that..
but my question is I have the same issue with the brake pedal "hissing" sound anytime I press the brake. This now only happened one day when I have the car sitting outside at work for 8 hours and it was -15 Celsius that day. after driving it I can hear that air vacume hissing sound I took it to dealer and they couldn't re-produce it. I park in the garage at night so today I didn't notice that hissing. I am thinking it has to do with the cold days? did you get your hissing issue resolved?
I also had mentioned to them that when I put the car from park to Drive or reverse to drive or reverse to park, the car makes a clicking sound and jerks. I took it in and they said they tested same thing on another c400 and its normal. However they did update a software in the transmission, but the click sound and slight jerk changing between gears is still occurring even after the transmission software update..
ps if you can please post that service history for the transmission valve that be great I can mention that to them, my warranty runs out in 4 months
thanks
I have the same hissing sound when I press the brakes, of course it's when I have the music down.lol
The transmission problem took some time to fix however it does jerk from time to time but not as hash so I don't always notice it. For those wanting to know about the C450 and C43, just remember that the C450 7G is a 7G Plus transmission and the C43 is the newer 9G Plus transmission whereas as the C400 just has the 7G without the Plus feature.
hi there I bought a used 2015 few weeks ago and I have taken it to dealer 2 weeks out of the 3 that I had it
rear side sagging, so they replaced the air shocks and caliberated it like 5 times so I will monitor that..
but my question is I have the same issue with the brake pedal "hissing" sound anytime I press the brake. This now only happened one day when I have the car sitting outside at work for 8 hours and it was -15 Celsius that day. after driving it I can hear that air vacume hissing sound I took it to dealer and they couldn't re-produce it. I park in the garage at night so today I didn't notice that hissing. I am thinking it has to do with the cold days? did you get your hissing issue resolved?
I also had mentioned to them that when I put the car from park to Drive or reverse to drive or reverse to park, the car makes a clicking sound and jerks. I took it in and they said they tested same thing on another c400 and its normal. However they did update a software in the transmission, but the click sound and slight jerk changing between gears is still occurring even after the transmission software update..
ps if you can please post that service history for the transmission valve that be great I can mention that to them, my warranty runs out in 4 months
thanks
Originally Posted by Cosworth2000
I have the same hissing sound when I press the brakes, of course it's when I have the music down.lol
The transmission problem took some time to fix however it does jerk from time to time but not as hash so I don't always notice it. For those wanting to know about the C450 and C43, just remember that the C450 7G is a 7G Plus transmission and the C43 is the newer 9G Plus transmission whereas as the C400 just has the 7G without the Plus feature.
Hmm my dealer has been saying that it's normal and that's how they are as far as the jerkiness goes... It's gotten better after a software update but i still feel it every day.. Do you think you can post the part number on here from your receipt? If the price is not bad, i might just pay out of pocket and swap it out rather than going back and forth with the dealer wasting my time.. thanks in advance!
Originally Posted by C400Benzeno
I would like to see the service paperwork or part number as well. I am having the same issues.
Sorry for late reply guys. I manage to find the paperwork it was in my car the whole time lost among some other paper and mail. I'll get that posted tonight. As for the hissing noise, the dealer was never able to reproduce the issue and there isn't specific trigger to make consistently happen. So nothing was done, as far as I was told or know. Since then, I haven't gotten the hissing noise anymore. I think it came back once or twice but it went away. Not quite sure what it is but it doesn't seem to effect the braking capabilities.
Sorry for late reply guys. I manage to find the paperwork it was in my car the whole time lost among some other paper and mail. I'll get that posted tonight. As for the hissing noise, the dealer was never able to reproduce the issue and there isn't specific trigger to make consistently happen. So nothing was done, as far as I was told or know. Since then, I haven't gotten the hissing noise anymore. I think it came back once or twice but it went away. Not quite sure what it is but it doesn't seem to effect the braking capabilities.
thanks bro, also question when you had the transmission body valve replaced did you get any error codes on your dash? when I mentioned this part to my service advisor she said usually there would be a code if there is an issue?
I get the odd jerk when it downshifts from 3-2 or 4-3 that's mostly if I don't have my foot on the gas and I let the car glide on a up hill slope...and as it down shifts I get that odd jerk..i don't know if this is normal or similar to your issue?
thanks bro, also question when you had the transmission body valve replaced did you get any error codes on your dash? when I mentioned this part to my service advisor she said usually there would be a code if there is an issue?
I get the odd jerk when it downshifts from 3-2 or 4-3 that's mostly if I don't have my foot on the gas and I let the car glide on a up hill slope...and as it down shifts I get that odd jerk..i don't know if this is normal or similar to your issue?
I didn't get any error codes on my dash. From what I have seen on the forums some jerking I think is acceptable and normal. Driving habits may need to change. However, I was getting really bad jerks when the car downshifts to a stop. Like whiplash jerking or someone suddenly stepping on the brake when I'm just trying to stop at a light. If it's really bad, have them take it out again and sit in there with them. When it jerks and you lunge forward coming to a stop ask them if you should feel like your on a roller coaster when simply stopping. Lol
I didn't get any error codes on my dash. From what I have seen on the forums some jerking I think is acceptable and normal. Driving habits may need to change. However, I was getting really bad jerks when the car downshifts to a stop. Like whiplash jerking or someone suddenly stepping on the brake when I'm just trying to stop at a light. If it's really bad, have them take it out again and sit in there with them. When it jerks and you lunge forward coming to a stop ask them if you should feel like your on a roller coaster when simply stopping. Lol
lol ok my isn't that bad to get a whiplash, its just minor here and there you can feel a slight shift..so ill monitor it but no my issue isn't like that..
my issue is them cant figuring out why the car cant sit all even, always one side of the car or corner is sitting higher/lower than other side..3 times in MB and they keep changing parts and constantly re-caliberating it and no aval...so far Im not liking my decision to buy a Mercedes
[QUOTE=dnguyen1437;7642278]Only took me forever but here is the part numbers used for the transmission valve body replacement. It should be attached to this post.
I have the same problem! Can you please write down the part number, because I can’t open the link. Thanks
I know there are other threads on transmission issues but I figured I would share my experience that I didn't see mentioned in other threads.
I took in my C400 last week for a broken wiper, brake peddle noises (air hiss and squeaking), and transmission issues that most have experienced.
When coming to stop and the car starts to downshift from 4-3 and 3-2, there is a noticeable jerk, like someone slamming on the brakes almost. Upshifts from 2-3 are shorter and also jerks. I usually drive in Comfort mode but I have felt the downshifts in S and S+ even worse. Feels like I'm gonna give myself whiplash.
My service manager updated me today and they think it's the clutch packs that are bad. They have already gotten some sort of approval from MB to start working on it. The clutch packs are ordered and they'll be tearing down the transmission this week. They'll be doing more testing after the clutch pack replacement. I'll update if this solves the issue since it may help others.
Hi, I have the same problem for my C400, that feels like when upshifting from 2 to 3 the RPM has a lagging (seems like turbo delay? it reaches to 2500 rpm then drops down below 2500 rpm to turn on the turbo). But I am not certain of how this may cause. Do you have any solution from your dealer?? Thanks!
Oh, also, second issue is the same as yours, that when the vehicle is downshifting specifically from 4-3 and 3-2, there is a noticeable jerk.
09-04-2018, 05:38 PM
