Home · 2011 Mercedes-benz C-class Phev · Complaints

What 516 owners told NHTSA about the 2011 Mercedes-benz C-class Phev

These are the actual owner complaints behind this car’s reliability verdict, filed with the federal government, unedited. They’re unverified reports, not confirmed defects: read them as leads for your pre-purchase inspection, not a diagnosis.

All (516)Crash / fire / injury (25)Airbags (269)Suspension (62)Fuel system (51)Body & structure (50)Electrical system (46)Steering (35)Lights (21)Brakes (13)Engine (11)Transmission & drivetrain (10)

Newest first · 516 complaints · page 3 of 21

Mar 21, 2023SuspensionBody & structure

My vehicle has been making very odd noises, the steering wheel keeps looking off center and the car is kicking/fishtailing at times without warning. Our mechanic has looked at the car SEVERAL times and finally discovered that the sub frame is completely rusted out and broken. We were told not to drive the vehicle anymore as it is extremely dangerous. After researching about this issue, we found that a class action lawsuit was filed in February 2023 for corrosion/rusting out of frames in 2010-2022 Mercedes Benz models. According to the information, Mercedes is refusing to cover the cost of the repairs and is not returning calls from customers effected by this issue. This information has been reported and added to the class action lawsuit. It was recommended that we report it here as well.

NHTSA ODI 11512961

Feb 17, 2023SteeringAirbags

Hi, I dropped off my car with Mercedes-Benz Dealership in Egg Harbor Twp, NJ back on Dec 21, 2022 and still waiting on recall to be fixed and while I'm without ever since that. Please look into this recall.

NHTSA ODI 11507821

Feb 8, 2023Suspension

Rear tires were down to steel belt after replacing August 1, 2022 and less than 10,000 mile wear. I took the car to a dealership for diagnosis. The rear subframe is completely corroded and failed causing extreme wear on tires and a DANGEROUS DRIVING SCENARIO. I’ve researched and see this is a common problem on these Mercedes cars. Why is there no Mercedes recall or accountability for this common issue?This is a serious issue that could cause serious accidents and bodily harm or death..

NHTSA ODI 11506266

Feb 6, 2023Airbags

Takata recall. The contact owns a 2011 Mercedes-Benz C300. The contact received notification of NHTSA Campaign Number: 16V081000 (Air Bags) and 19V010000 (Air Bags). The vehicle was taken to a local dealer for the recall repair; however, the vehicle remained at the dealer awaiting parts for the repair. The manufacturer was contacted and was unable to confirm when the parts would become available. The contact had not experienced a failure. Parts distribution disconnect.

NHTSA ODI 11505784

Feb 5, 2023Body & structure

Took my 2011 C300 4matic to a local mechanic after I noticed a dramatic pulling sensation to the left after braking. After mechanic's inspection, I was informed that the rear subframe was rotted out and that the vehicle is unsafe to drive. I still have the car available for inspection of the rear subframe. The rear subframe caused the pull to the side under braking, which alone could cause an accident. Since it also connects the suspension to the frame of the car, at any point a critical suspension component could break off from the subframe, likely causing total loss of control of the car and potentially an accident. I also took the car to a Mercedes-Benz dealership where they confirmed that the rear subframe would need to be replaced and that the car was not safe to drive. I contacted Mercedes-Benz corporate, but received no support. I was only informed that they are aware of this issue, but they will not assist in any way since there is no recall issued. I provided them with copies of the quote from the dealership.

NHTSA ODI 11505704

Feb 1, 2023Body & structure

The contact owns a 2011 Mercedes-Benz C300. The contact stated while driving at approximately 55 MPH and slowing for traffic, the rear end of the vehicle started to drift to the right. The contact heard an abnormal sound coming from the rear driver’s side of the vehicle. The contact stated no warning light was illuminated. The contact had driven the vehicle to a local dealer, where it was diagnosed and determined that the entire rear subframe needed to be replaced due to extensive corrosion. The vehicle had not been repaired. The manufacturer had been informed of the failure. The failure mileage was approximately 85,000.

NHTSA ODI 11504976

Feb 1, 2023SteeringTransmission & drivetrainEngine

Electronic steering locks are failing in these cars at an alarming rate. When it fails, the car will be stranded or if driving the car will completely lock the steering and take away control from the driver. This is a safety issue that Mercedes should be recalling and fixing because it will take people's lives away. Mercedes is aware of this issue but is failing to recall it and considering it as non-safety. When manufacturing the Electronic Steering lock, Mercedes used cheap parts that are prone to failure. This issue affected many years and models of their cars but only recalled a few cars. Once failure occurs, the car will not start and it will be required to tow it to a dealership where repairs over $2000 will be needed to fix this SAFETY issue.

NHTSA ODI 11505048

Jan 25, 2023SuspensionBody & structure

My 2011 c300 has a rotted rear subframe making the car not able to be driven. It has major ,life threatening, costly damage and this issue already has a recall all over the world but not in the United States.

NHTSA ODI 11503537

Jan 24, 2023Lights

The contact owns a 2011 Mercedes-Benz C300. The contact stated when he started the vehicle, the driver side taillights were inoperable, and the taillight warning light was illuminated. The contact examined the taillights and noticed that the wires were melted, and the taillight assembly had melted as well. The dealer was contacted and stated that the vehicle was serviced under NHTSA Campaign Number: 14V177000 (Exterior Lighting). The contact received no additional assistance. The vehicle was not repaired. The manufacturer was not contacted. The failure mileage was 90,000.

NHTSA ODI 11503441

Jan 20, 2023SteeringSuspensionBody & structure

Rear sub frame and suspension welds have cracks and are broken a loose which when having to put on brakes suddenly cause car to servely pull and twist which can cause a bad accident or worse.

NHTSA ODI 11502894

Jan 18, 2023Body & structure

Subframe rots prematurely. Known issue to Mercedes Benz and has been recalled and covered in both Germany and Canada.

NHTSA ODI 11502449

Jan 10, 2023SuspensionBody & structure

The contact owns a 2011 Mercedes-Benz C300. The contact stated while driving approximately 60 MPH, the brake pedal was depressed, and the rear end of the vehicle pushed out. The contact looked underneath the vehicle and noticed that the subframe was rusted. The vehicle was taken to an independent mechanic who informed the contact that the control arm had detached. The contact called the local dealer, but the vehicle was not diagnosed or repaired. The manufacturer was contacted but no additional assistance was provided. The failure mileage was approximately 105,000.

NHTSA ODI 11501116

Jan 9, 2023Electrical system

Due to apparently deficient sunroof water drain system design, rainwater and condensation entered the passenger compartment under the carpeting, potentially damaging the vehicle's electrical wiring. The vehicle is available for inspection upon request. A dealer has inspected and confirmed the damage. Initial symptoms of the problem were wet carpeting and the sound of water sloshing around under the floor of the passenger compartment.

NHTSA ODI 11500865

Jan 3, 2023Body & structure

While driving down the highway at approximately 55mph, my car abruptly swerved left nearly causing an accident with the vehicle in the opposite line. My car was taken to my personal mechanic where he found the rear subframe to be completely broken on the left side due to severe rusting. Luckily the break lines were not damaged during the breakage. I investigated this issue online and it seems to be a very common issue in which no recall has been issued. This is a very serious safety issue that very easily could have resulted in a fatality on myself or other and future failures. It is my understanding that Mercedes Benz has a 30-year corrosion warranty but the subframe is not covered. How can this be?

NHTSA ODI 11499922

Jan 3, 2023

The control arm is currently freely hanging. The reverse subframe rusted out where the control arm connects to it causing severe swaying when braking.

NHTSA ODI 11499936

Dec 31, 2022Suspension

I was teaching my 16 year old son how to drive when he got his learners permit . When we got onto the highway a car cut him off and he had to apply a firm steady brake . When breaking the car swerved from the rear into the other lane , nearly striking another vehicle . This also resulted in a loss of control when applying heavy breaking after I had him pull over and I took control of the vehicle once I was able to get the car to the shop I pulled the rear wheel s off and inspected the brakes , which were found to be in good condition . I looked around the vehicle and noticed where the rear driver side subframe connected to the control arm broke off from a manufacturer defective weld or poor selection of materials . component. Upon inspection both sides are perforated and have lost structural integrity. Many other vehicles of the model type have reported similar issues online. This is a serious safety concern that will happen to 100% of these vehicles. A recall needs to be issued by Mercedes for this immediately. This vehicle has very little rust anywhere except at these connections .

NHTSA ODI 11499607

Dec 28, 2022SuspensionBody & structure

The contact owns a 2011 Mercedes-Benz C300. The contact stated that while driving at an undisclosed speed, the rear driver’s and passenger’s side wheels swayed left to right, and the rear driver’s side wheel detached from the suspension. No warning light was illuminated. The vehicle was taken to a repair shop where it was diagnosed that the rear subframe was rusted and needed to be replaced. The dealer was notified of the failure and the contact was scheduled an appointment. The manufacturer was notified of the failure and the contact was awaiting an estimate. The contact was provided a case number. The failure mileage was 88,640.

NHTSA ODI 11499171

Dec 7, 2022Suspension

Tried to get alignment and was told rear sub frame is rotted. Must be replaced. Car is garaged. Serviced at dealer. This shouldnt be happening. Car was involved in accident (mainly passenger doors damaged) which triggered us to need to get new tire which alerted us to alignment cant be completed and told to not drive car it's not safe due to rotted subframe.

NHTSA ODI 11496482

Nov 27, 2022SuspensionTransmission & drivetrainBrakes

The subframe and the brake lines are very faulty in this car when it comes to its design. The subframe and brake lines rust easily and are cheaply made for this car. My car break down while driving making it hard to have pressure on the brakes. My incident was around the school area. There were no accidents or collisions Involved. It could happen to adults and children. The dealer never confirmed this problem before selling it to me. Another manufacturer told me about this problem. The car showed warning signs like the braking system and brake fluid. The brake fuel was leaking. The problem appeared when I started the car.

NHTSA ODI 11495007

Nov 17, 2022Suspension

I was driving my 2011 MB C300 40 MPH on a straight suburban road when the light turned red. I applied the brakes and heard a clunk from the rear. Surprisingly, the car swerved with a right turn yaw moment. Normally I enjoy driving my car, but that never happened before. So I tried it again in the next block and it yawed again. That’s not right. My mechanic happened to be just down the road so I pulled in. He told me that the rear subframe had rusted out and the car was unsafe to drive. Furthermore, he would not attempt welding it because the metal is too far gone. A new replacement part is unavailable from the dealership and back ordered from Germany for months. Used part will also be rusty. My car with 77k miles on it is suddenly worthless. Mercedes-Benz “The Best and then Nothing”

NHTSA ODI 11493982

Nov 9, 2022Suspension

The rear subframe rotted and broke as I was driving. I almost got into a bad accident. This apparently is a common & deadly issue that MB is aware of. Unacceptable that there is not a recall.

NHTSA ODI 11492864

Oct 30, 2022Suspension

While driving home last night (with passenger), I experienced a sudden pull to left and wobble\oscillation of the car when I made steering corrections to prevent vehicle from going into oncoming traffic. Car seemed to behave normally except whenever I applied the brakes. I proceeded home, where I inspected for the obvious such as brake calipers, pads. rotors etc. Then I removed the rear left tire. This was due to a clunking sound that seemed to come from that area. Everything looked OK until I saw a front lower suspension part (a plastic covered pressed metal strut connecting the lower part of the wheel\rotor assembly to large U-shaped frame member which had multiple welded attachments and brackets) just hanging there unattached on one (forward) end. The bracket it was bolted to was just sheared off. Looked like it rusted to the point of finally tearing itself off of the frame. There was no warning of this condition either by sensors/lights/etc. or the performance of the vehicle when driving it. The defective braking action was sudden. This is NO SMALL ISSUE! After reading of the numerous reports of this very same problem I have to say I am amazed that NOTHING IS BEING DONE TO PREVENT THE FIRST DEATHS AND INJURIES THAT WILL MOST LIKELY OCCUR FROM THIS. This is a danger to the occupants of the principle vehicle, pedestrians, as well as other vehicles in the immediate vicinity, moving or stationary. This can happen at high speeds, slow speeds, in traffic with other vehicles around the car or humans on sidewalks. I can clearly see that this is not a small repair as it looks like the entire rear assembly would need to be taken apart and reconstructed in order to replace the part. I have also read that this issue is not only common but that it has been recalled in Canada and Europe by Mercedes for repair. I guess we are waiting for the first deaths to occur before our American safety agencies can take action? Really?

NHTSA ODI 11491541

Oct 28, 2022Suspension

Rear suspension crossmember mounting point for one of the control arms broke off allowing control arm to fail. Possible entire wheel assembly could now fail creating dangerous driving conditions especially at higher speeds. Took to a shop and confirmed. Called Mercedes dealership and they said it was not covered by a recall even though in Europe I believe it is. Many websites have said this is an ongoing and common problem.

NHTSA ODI 11491255

Oct 26, 2022Suspension

I have a 2011 Mercedes C300 that I purchased as a Certified Vehicle - this car was purchased at The Mercedes Dealer in Kansas City. I believe I purchased it around 2013 - I have recently found out that the rear sub frame is completely rusted out. I have had the car repaired at my auto shop - Not a MB dealership, as there was not a dealership that was able to see the car in any reasonable amount of time and the car was not safe to drive. The only way I found out about this rusted out subframe was due to the control arm breaking off - This car was very dangerous to drive and in essence, it is probably a good thing that the control arm broke as this could have resulted in a loss of steering on the vehicle and a very dangerous accident! I have been reading online and speaking with MULTIPLE people who have had the same situation with this rear subframe. This is CLEARLY an issue with MB and clearly an issue that they have been made aware of. When I called the NMB service department they were a month out to just look at the car - and the part is on back order I was told - which CLEARLY indicates a lot of these rear sub frames are being replaced. I am attaching various articles / forums online that I just, at a glance, composed a list of. There are a TON of stories of these sub frames rusting out for various models. Seems to be tied mostly to the C300 vehicles. I am attaching pictures of this rusted out subframe and an invoice that I paid to have the car repaired for this issue. The ironic thing is when I was at this auto shop, there was another C300 sitting out front that had just had the same rusted out subframe replaced. Mercedes has a recall in Canada for this SAME issue and other countries have acknowledged this is a major safety issue. A rear subframe should not rust out and leave the driver with no way to steer the car. Mercedes has refused to acknowledge this is an issue in the US.

NHTSA ODI 11491041

Oct 24, 2022Body & structure

The contact owns a 2011 Mercedes-Benz C300.The contact stated while driving 65 MPH, the vehicle was swinging from side to side. The contact desperately pumped the brake pedal, and the vehicle was able to stop swinging. The contact checked the vehicle and notice that the subframe was fractured on the driver’s and passenger’s side rear. The dealer was contacted and stated that they were aware of the failure; however, there was no recall on the vehicle for the failure. The manufacturer was not contacted. The failure mileage was 101,058.

NHTSA ODI 11490618

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Working with the data? Download all 516 complaints as CSV · fetched from NHTSA July 21, 2026

How to use these: a complaint is one owner’s report, filed voluntarily and published unverified. Patterns matter more than any single story. If several owners describe the same failure at similar mileage, put that system at the top of your pre-purchase inspection list. Back to the full 2011 Mercedes-benz C-class Phev verdict →