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

Rusted left rear ear of rear subframe.

NHTSA ODI 11489990

Rear Sub frame faiIure / rusted and rotted On this site alone there are complaints listed under 3 different heading Structure (30) / SUSPENSION (38) / UNKNOWN OR OTHER (20) all related to the rear sub frame. not to mention 100's on the web. I nearly died when I hit the brakes the car lurched to the left at highway speed. My mechanic told me that the rear Subframe was rotted and the rear control arm is no longer connected to the sub frame He insisted that the car is UNSAFE to drive. He was very surprised as the car only has 70,000 miles on it and in good shape with no rust anywhere else on the car. I did a quick search of the issue on the web and immediately found that MB has had this issue across the world in various models manufactured in 2011-2014. Presently, there are recalls in Germany and Canada for this issue. I contacted my MB Service department and was informed that no recall for this issue exists in the US and they would not cover the costs to repair. The repair could cost between $5k to $7k They told me that I would need to contact MB North America Customer Service. I find it amazing that MB Service, Dealers and North America HQ are all aware of this issue but the Company will not issue a recall or stand behind their product. This not some minor defect. When a major structural component of the car is compromised the lives of vehicle occupants and others on the road are at risk of death due to a major accident. The vehicle is now undriveable and will cost several thousands of dollars to repair. MB is fully aware of this issue and refuses to do anything about it. NHTSA needs to address this issue and make the Manufacturer stand behind their Quality pledge which as a consumer you are paying for when purchasing what you expect to be exceptional German engineering and what you are given is a a product with a known defect that will not be addressed.

NHTSA ODI 11489986

There was a recall on airbags on this model the C350 2011 and the airbag is now back on

NHTSA ODI 11489465

What component or system failed or malfunctioned, and is it available for inspection upon request? Rear subframe has rusted out and left side arm has separated- my car has been routinely maintained and primarily housed in garaged parking. It does not have a history of flood or water damage. How was your safety or the safety of others put at risk? My steering and breaking was impacted even at low speeds < 30 MPH. Has the problem been reproduced or confirmed by a dealer or independent service center? - Vehicle failed a Maryland state safety inspection and was deemed unsafe to drive. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Yes, inspected by Maryland state certified safety inspector Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? I noticed decreased accuracy in my steering upon breaking and decreased function in breaking- my inspection revealed that all breaks were intact and working.

NHTSA ODI 11489493

When fuel tank is greater than approximately 3/4 full there is a strong fuel odor that seems to emanate from the rear passenger side of the vehicle; at lesser fuel quantities the odor is not noticeable. On one occasion I detected what appeared to be fuel dripping from underneath the vehicle. Took vehicle to dealership for troubleshooting and was informed "fuel leaks at the fuel pump" and it was recommended that the fuel pump and fuel sender be replaced. Additionally, the leak apparently damaged the electrical wiring harness to the fuel pump and that also needs to be repaired. There were no warning lamps or messages displayed that alerted me to this problem. Obviously, this is a hazard to safety.

NHTSA ODI 11488047

rear subframe rotted and broke

NHTSA ODI 11488116

the rear subframe rotted away

NHTSA ODI 11488118

A dealer inspection found a rusted away rear subframe with holes in it and near total failure and undriveable. The part is being removed by a dealer and its whereabouts after that will be unknown. Garage kept and continually cleaned a car such as this should not experience the visible decay it has after such a short time. A defect definitely existed in the sub-par metal products used during production. This issue presents a catastrophic situation if not realized in time. A factory recall is in order.

NHTSA ODI 11487027

Rear Subframe Rot. The vehicle was purchased July 2021 from Automax Of Frederick Maryland. I took the car to Euromotors of Bethesda and they informed me about the issue so I took it back to the dealership because the car was sold to me like this and the owner of the dealership let me know that his "guys" would have never passed it in the MD inspection if a hole was about to be there or severe rust. However it was still sold and now I have the problem of where one of my control arms are rusted out and the car is not safe to drive. The dealer also let me know that the rust was just "surface rust" and it was nothing to worry about. The dealer ask me to bring the car in to inspect and lifted and let me know they would put a ticket on it if the car gave me any problems they would take care of it. Never got anything from them.

NHTSA ODI 11486831

Had to replace the rear sub frame due to extensive rust and erosion. Major safety concern. This was brought to my attention at a routine maintenance service appointment. Almost as is they knew they should be looking for this problem. We are the only owners of this car. It is a garage parked car. No rust elsewhere just at the welded connection on the rear sub frame.

NHTSA ODI 11486722

Rear subframe rusted to the point car is not drivable

NHTSA ODI 11484571

--the rear subframe is severely rusted at 2 spots where the suspension and the body come together. If hit a hard bump or pothole it could break and cause a large safety issue. The rear subframe is $4751.00

NHTSA ODI 11484438

I was driving my C 2011 MB and suddenly when applying the Brakes the car had a severe pull to the left and a loud noise from the rear driver side wheel. I made an appointment with my mechanic to have the issue looked at. There were no warning lights or other symptoms until basically the complete failure of the rear suspension. My mechanic informed me that the rear Subframe of the suspension on the vehicle had completely rusted out and the components holding the brake assembly and sway bar were almost at the point of becoming disengaged from the vehicle. He stated that the car is unsafe to drive. He was very surprised as the car is garage kept an in good shape with no rust anywhere else on the car. I did a quick investigation of the issue on the web and immediately found that MB has had this issue across the world in various models manufactured in 2011-2014. Presently, there are recalls in Germany and Canada for this issue. I contacted my MB Service department and was informed that no recall for this issue exists in the US and they would not cover the costs to repair. They told me that I would need to contact MB North America Customer Service. I find it amazing that MB Service, Dealers and North America HQ are all aware of this issue but the Company will not issue a recall or stand behind their product. This not some minor defect. When a major structural component of the car is compromised the lives of vehicle occupants and others on the road are at risk of death due to a major accident. The vehicle is now undriveable and will cost several thousands of dollars to repair. MB is fully aware of this issue and refuses to do anything about it. NHTSA needs to address this issue and make the Manufacturer stand behind their Quality pledge which as a consumer you are paying for when purchasing what you expect to be exceptional German engineering and what you are given is a a product with a known defect that will not be addressed.

NHTSA ODI 11484455

Rear Sub-Frame completely rusted out on car that has only 68800 miles and garaged kept since new. The suspension failure is an obvious engineering issue. No rust anywhere else on the car. The vehicle sways and bangs there is almost no metal left on the framework that all of the other rear suspension components mount to and rely on for stability. I have pictures to show what an obvious pre-mature failure this is from a touted high end auto manufacturer. Mercedes Benz should be investigated and made to repair these vehicles.

NHTSA ODI 11483787

Rear subframe of vehicle completely rotted/rusted out and destroyed. Was driving at around 60mph and all of the sudden, went to step on the brakes and the car swerved across the highway uncontrollably. Initially thought this was my brakes, but turns out, it is the rear subframe. Took it to a mechanic who said the car is not drivable and showed me how badly the subframe is destroyed. This is due to a Mercedes Benz manufacturing issue where they tried cost cutting which turned out very poor quality materials for this very important assembly. My car only has ~90,000 miles and is just about 10-11 years of age. This issue should never happen for a vehicle with such low miles and such a short life, especially from a prominent and distinguished automotive company. This is a MASSIVE SAFETY CONCERN, and I am lucky that I was not involved in a major accident where people were killed or seriously injured. I have research online about this problem, and turns out, it is VERY COMMON with this body style c300 ('08 - '14). There are hundreds, if not thousands, of individuals within the USA who are having this exact same issue with as little as 60,000 miles. Most are happening around the 90,000 mile mark however. It is astonishing how this subframe was not recalled by now and how Mercedes USA has not taken responsibility for this. In fact, this is a known issue by the manufacturer, and has actually been recalled in Canada (but not the USA?).. This issue needs to be addressed and recalled IMMEDIATELY before people are killed or seriously injured, and before more of these parts break. Please look into this very soon and contact me with any questions.

NHTSA ODI 11483600

when braking the back of the car all of a sudden tried to break out to the right. After towing it to the dealer I was told that the subframe was broken due to corrosion. The car is otherwise in good condition without any visible sign of corrosion. When searching the internet for the problem I learned that a lot of these cars have the same issue and that there are recalls for it in Canada and Europe. I'm just glad that I didn't get into a bad accident, since this came without warning and the dealer didn't make me aware of the problem even though I did every service for the car with them for the last almost 12 years.

NHTSA ODI 11483285

I was driving down the road when a deer ran out into the roadway ahead of me. I applied the brake firmly and hear a "pop" and the car suddenly changed lanes. I was able to recover without much of an incident but applying the brakes from that point on caused the car to "steer" into a new direction. I took the vehicle out to a friends farm and jacked it up to find that on this car with zero other corrosion issues that the mounting point for one of the rear suspension arms had rusted at the weld and broken off the sub frame. I should note that the rest of the underbody was inspected and the rear subframe is the only place that has any corrosion. Research into this issue over the past few months has lead me to countless people being affected by the same issues. This is not an isolated case and it needs to be addressed by the manufacturer before it causes a fatal accident (if it has not already).

NHTSA ODI 11482982

The contact owns a 2011 Mercedes-Benz C300. The contact stated while having a routine brake service performed, the contact was informed that the driver’s side rear subframe was rusted. The contact was informed that the failure might puncture the fuel tank. The vehicle was not repaired. The manufacturer was informed of the failure but provided no assistance. The failure mileage was approximately 157,000.

NHTSA ODI 11482098

Manufactory defect on w204 Chassis Mercedes Benz rear sub frame rusting allowing control arm to brake free affecting safety and drivability control loss, which has or could lead to severe accident. There no recalls for this defect and is a common issue with materials on back order for the rear sub frame, vehicle Is not drivable until frame is replaced.

NHTSA ODI 11481664

My C300 2011 is having rear suspension problem which is unsafe to drive. I took in my car for my usual maintenance check and was told by the mechanic that the rear left driver side suspension is rusted and rotated out, to the point that it can break off and cause an accident. As Mercedes product, even the mechanic was surprised to see this happen on this car. Not surprised the dealer told me there is no recall at this time. I am still waiting for a quote but from what I've seen other people complaining with the same exact issue in same make and model. I have attached pictures just in case.

NHTSA ODI 11481426

I started to smell gas after filling my tank. Once the gas level went down, the odor disappeared. I took car to dealer who said car needs new gas tank (issue on top of tank) and cost is approx $5K for parts and labor. I started reading about same exact issue on same C300 model and year 2011. I was advised that car with high mileage of 114,000 was not worth repairing even though there are no dents, cosmetically very nice, new tires, always dealer maintained. I have the dealer inspection paperwork

NHTSA ODI 11481477

The contact's client owns a 2011 Mercedes-Benz C300. The contact stated that the vehicle's owner had complained of an abnormal fuel odor coming from the vehicle. There was no warning light illuminated. Upon inspecting the vehicle, the contact discovered that fuel was spraying out of the fuel pump onto the exhaust. The contact was able to replace the fuel pump and correct the failure. Upon investigation, the contact discovered NHTSA Campaign Number: 12V557000 (Fuel System, Gasoline) which he linked to the failure. The dealer nor the manufacturer had yet to be notified of the failure. The vehicle had been repaired. The failure mileage was approximately 142,000.

NHTSA ODI 11481256

The contact owns a 2011 Mercedes-Benz C300. The contact stated that after refueling the vehicle and driving a short distance, there was a burning odor coming from inside and outside the vehicle. The traction control warning light was illuminated. The contact had taken the vehicle to a certified mechanic who replaced the fuel cabinet. The burning odor persisted. The contact was informed that the failure was related to NHTSA Campaign Number: 12V557000 (Fuel System, Gasoline) however, the VIN was not included. The manufacturer was made aware of the failure. The approximate failure mileage 12,800.

NHTSA ODI 11481021

The driver side rear tail light wiring melted the tailight housing. This component was already replaced as part of a previous recall, but apparently Mercedes is not properly fixing the issue. They refuse to fix it for free, because they already "addressed" the recall. Looks like they are putting cars back on the street that could catch fire.

NHTSA ODI 11480828

I am contacting you about a certified pre-owned car I had purchased from Mercedes Benz Cincinnati. Following my most recent routine maintenance visit to the dealer, I received an email from Mercedes stating that they had identified that the rear subframe on my Mercedes C300 4Matic needed replacement and it was not safe to drive. It turns out that the two joints on the subframe were corroded. This type of a problem is not expected for a professionally maintained certified car by Mercedes that is at 58,481 miles. The issue has nothing to do with standard wear and tear, or user negligence, and it stems from the material used in the specific component. There is no other area on the vehicle that is displaying even the slightest amount of corrosion. The mechanic said that this is to do with the properties of the materials selected for the manufactured part, they have been seeing many cars of the same year with the same exact problem, and if the subframe joints were to break while the car is in motion, it could potentially cause a fatal accident. There were no warning lamps, message or symptoms of the problem prior to the failure. I contacted Mercedes and asked them to address this problem. After months of back and forth, I was told there were no safety recalls, and the car was out of standard warranty period. I was also told that the part was not currently available (and was on back order). As you may know, the subframe's job is to distribute high local loads over a wider area of the body structure and its failure could result in fatal accidents. The internet is full of customer complaints on this issue, yet there are no safety recalls issued.

NHTSA ODI 11480406