Hey guys,

So I bought a brand new 2020 C43 back in June, already have 9800mi on the car but from day one I ran into issues out of the norm or it might just be me being OCD. At Hwy speeds there’s a vibration in the steering wheel that you can also feel in the pedal. You start to feel it around 67-78mph, once I hit 80-90mph it almost goes away but after I climb past 90mph it gets worse the faster I go and you really start to feel it. Issue #2 car wants to have power when it feels like it. Trying to catch up to a Kia Rio feels like a mission. Car has only hit 384hp once and likes to sit around 320-370ish range on the gauges. Issue #3 the gear shifts feel way to harsh. From getting off the line to coming to a complete stop doesn’t matter what mode you’re in even tried controlling it in manual mode still feels like a tranny from GM’s pick up line. Took it to the dealer told me they can’t test it at Hwy speeds because the interstate is too far away but they’ll do their “best”. Got the car back the next day service advisor told me the tech didn’t find any problems only thing he noted that it looks like my front left tire is taking wear from cornering. So he balanced the tire for me to help try and lessen the vibration. The power side he told me the car is performing how it should be there’s nothing wrong. The drive home it still vibrates and performs the way stated above. I have a 2008 CLK550 cabriolet and honestly I feel like that tank feels Faster/more like a AMG than my C class. This is my 9th Benz and honestly I’m just ready to put it away.

that’s a wrap on all my problems (: thanks for hearing out my b******* for not going with a C63 S let me know if y’all are having the same issues or not.

 

Have the same vibration at highway speeds.

Was present on the 2018 I had (which was a lemon). Present on my ‘20 as well. It must be a trait baked into the DNA of the C43.

I also am down on power. Car is only making 267 horsepower (max), and I had to thrash it within an inch of its life to achieve that.


The C43 is mostly well-reviewed from a performance perspective, and I thought my first car’s issues were atypical because it was such a mess.

After having my second C43, it just seems not very well-sorted. The more you spend time with it, the more it gets exposed. I almost went back to a C63 before getting my ‘20, but I wanted the AWD.

 

Alright so I’m not crazy. I’m taking the car back to the dealer tomorrow. The vibration feels like a CV axel issue though could be need dry. I noticed a lot of things like my drivers door, front/rear lamps, front/rear bumpers are misaligned. For spending $65k + Then seeing all the imperfections makes me feel like they stopped caring about quality.

 

Sounds like you have have a driveshaft issue. There have been a few members with similar problems as you (though these seemed to be PFL c43 cars if memory serves). Nonetheless, this is not good or normal and you should push the dealership to fix the problem since it is under warranty.

 

I had fender badging fall off my '18, my interior reading lights didn't work, the windshield wipers over-traveled and hit the A-pillar in heavy rain, and some kind of adhesive started seeping through the interior door panels (it looked like salty, white sweat stains) every few weeks. It finally stopped seeping, but it left dark stains behind.

Had to have all the rotors replaced within the first month of ownership due to corrosion, permanently baked on rust that I couldn't eliminate off the rotor faces no matter how many miles I put on the car, and a vibration through the brake pedal. Also had to have the rear differential replaced 3 times. Among other things lol!

My '20 C43, on the other hand, was rock solid for the first few months. All the doors shut with a nice "thud," all the buttons and switches feel very positive/crisp, the leather on the interior is immaculate, paint has a beautiful finish, and the panels fit very nicely.

Then, the battery started to crap the bed, and I started to lose power (have a thread on it). Taking the car to the dealer on Thursday.

 

The vibration, as Zibby43 noted, seems to be almost normal for the C43. I've had it too. It has been a recurring complaint for all of the 4matic (but not the 4matic+) across MB vehicle lines. There are similar complaints from GLC43, C300, and even E-class owners with 4matic. It seems to be traceable to either driveshafts that need re-balancing and/or bad rear differentials that need to be replaced. I strongly suspect that MB ended up with a large number of bad driveshafts and differentials, and once the warranty claims started popping up, should have immediately known there were material issues. I also suspect that they have taken the time-tested approach of ignoring the problem and continued to used the defective items, figuring that most people wouldn't notice, wouldn't complain, or that the problems could be dismissed as "normal" by the service departments. The number of warranty claims will only be a fraction of the total defective out there, so it's the most cost effective approach form their point of view. Happens like that across multiple industries, but is still a crappy thing to do from a customer service perspective. Not excusing MB at all, because it's a known issue that should be a TSB at a minimum, but it looks like MBUSA has chosen to pretend it isn't there. I would suggest trying a different dealership if that is in any way reasonable for you. Some are just lazy and apathetic, and some actually know how to treat the customer.

The transmission harshness really is normal. It's just a side effect of the wet-clutch design. Some shifts will be smooth, others will bang through the gear change, especially the first three in this car.

The issue with power delivery could be due to any number of things. I see your profile says you're in Florida. High ambient temps and high humidity are going to lead to reduced power. Your car may be more sensitive to it than other vehicles, and there might even be changes for the 2020s in the factory mapping that are pulling power more than previous years when the ambient temp is higher.

 

Definitely sounds like a drive shaft. I just dropped my '19 off for its first Service A yesterday and 2nd drive shaft in 6 months

 

has there been changes to the drive shaft? Seems pointless if the issue was not addressed and keep replacing with faulty ones.
As far as power goes, why don't you take it to a dyno and get a clear answer instead of going with the ondash system? I don't trust that boost gauge and the hp/tq thing.

 

Did the driveshaft actually fix the issue first time around? how about the second time around lol

 

Definitely helped the first time around. It was so bad from stock even the tech that I took a drive with to demo the issue was in shock. I then noticed it was pretty much gone although every once in a while I can hear/feel it again. Some days are worse than others.

Of course I went out for a drive with the foreman yesterday and it didn't act up in over 30 minutes, so i'm not thinking they are going to replace it a second time just yet.

If you have a rhythmic vibration that you can feel, especially up through the seats, it's like the driveshaft. This is apparently a very common issue on the C-class (C300 -> C63). Most dealers should know what you are talking about if you bring it up to them. Mine shouted "Driveshaft" when just explaining the problem over the phone the first time!

 

hey there which dealership did you get your car serviced? I have a 19 and yes I feel these rhythmic vibrations

 

There is a whole thread talking about this issue.
See if the original poster in that thread provides answers that may be helpful
https://mbworld.org/forums/c450-c43-...ise-issue.html

 

thanks I’ve already been down this road didn’t get the answer I needed. Was hoping I can get a dealership to help actually replace it instead of giving me”it’s normal” answer

 

Unfortunately, that is the response I always get from them. I don't even want to bother at this point. Dealing with it later. Anyways, good luck on getting yours fixed though.

 

I did some more testing today and would like to share my latest findings.

Recap of the problems
1. The late and sluggish automatic shift from first to second gear, which jerks me forward in my seat. This behavior is not repeatable — sometimes the shift is crisp and smooth.
2. The vehicle intermittently failing to respond to my manual upshift request from first gear to second gear when I’ve got the accelerator pedal pushed pretty far down to the floor.

Findings from today

1. The late/sluggish upshifts still happen, but they are not as jarring as they were the last time I experienced them. Perhaps the shifts are improving as I accumulate more miles on the car.
2. The shifts are generally crisper when I have the Dynamic option (rather than, say, Sport) selected for the Drive parameter in my Individual configuration.
3. The vehicle still fails to respond to my upshift requests sometimes, and this issue is not limited to the shift from 1st to 2nd gear. In this video (had some upload issues, so it's a video of a video! ), you can see that the vehicle does not respond to my first click of the upshift paddle in 3rd gear. Only one I click it a second time does the vehicle upshift to 4th.

 

Even when in manual mode, the car will not allow you to "short shift" and shift earlier than what the system deems acceptable. Easy to duplicate, start out slowly in first gear and gradually come up to speed and begin upshifting at 10 MPH, you probably will not get past second gear without first gaining more speed. The system will not allow you to lug\load the engine. You were apparently just at that threshold in your video.

My car has the analogue cluster and the shift light will flash red when I try to prematurely "short shift" into higher gears.

The car is never fully manual; the ECU employs restrictions on both upshifts and downshifts and will save you from over-revs with a soft throttle-cut when you hit redline. More like an artificial manual you might say.

Interested to know your results after switching to ESP Sport and ESP off settings.

 

Yeah that is odd that it doesn't respond to your upshift. You were at a good rpm to do it. It didn't refuse the shift. If you try to short shift too early the entire digital dash flashes red (at least in my C63S) to let you know that the shift wasn't possible as the resulting rpms would have been too low, but I didn't see your instrument cluster flash. I'm thinking you may have a bad shift paddle, which can happen. Normally they can wear out over time and the switch gets faulty, but yours could be faulty from the factory.

 

Yep, my cluster will indeed flash red if the system refuses the shift request. As you noted, the system did not refuse my request in the video, but it still didn't shift. I find it difficult to reliably replicate the problem, so I don't think I'm ready for a dealership visit yet...