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

Rear subframe , so I went in for an alignment and was quickly notified and denied service due to my rear sub frame being broken. Car is reported to be unsafe by the tire company.no lights etc. My family and I could of seriously been hurt. I can retrieve a statement from dun tire in auburn and from mercedes. They are charging me 641.00 and I'm without a vehicle for 2wks

NHTSA ODI 11624585

Interior door handle becomes inoperative due to breaking of some internal element. This prevents leaving the vehicle. Of concern is that in case of emergency, the occupant cannot exit the vehicle. If power is affected, the windows cannot be lowered which is the only way to exit using the exterior door handle. This is a well known defect of this series of Mercedes Benz to which the manufacturer has not accepted responsibility.

NHTSA ODI 11593665

So i was using my car daily for go to work and I was on the highway and they happened a accident in front of me so I have to slow down due to the accident i was going 70 miles per hour and when made a hard break my car turn sideways due to the rear subframe was broke and I dint even notice that the part was rotten they i start looking online and I noticed that the majority of those car come with that factory issue.

NHTSA ODI 11586041

Non operating. No tags . No plates.

NHTSA ODI 11571578

The subframe has rusted/fallen off. This is incredibly risky as the car cannot be driven safely and it happened without warning. My mechanic said it is not due to any driving incidents but through rust occurring on Mercedes' subframes, which are flimsy. It has been inspected professionally by a mechanic. There are NO warning lamps. This could kill someone on the highway as while braking the car veered left and right. I had small children in the car we all neck pain from the car veering while stopping on the highway. I have taken good care of my vehicle and have all maintenance current. This is a fault with the material on the subframe. For MB: All the subframes are on backorder and are incredibly expensive to fix. I have a video of the damage from the mechanic if needed.

NHTSA ODI 11553395

2011 C300 4matic Sport I'm very concerned about the front subframe after going over the invoice and everything that was replaced on the rear subframe due to a recall Mercedes issued. But wait doesn't the whole subframe have severe rust corrosion all throughout yes it does per mechanic/technician. I'm having steering issues while driving the vehicle when applying the breaks the vehicle pulls very hard to the left the whole car swerves to the left very dangerously. After getting it checked out the mechanic/ technician pointed out that the control arm snapped from the Front subframe due to severe corrosion. I'm not understanding how the recall was only for the rear subframe only. The whole entire subframe is severely rusted. Front subframe which may experience premature wear of the front axel carrier and a fracture risk, potentially resulting in sudden loss of steering control. After internal endurance testing determined the front axle carrier supplied for certain Mercedes SUV’s and cars may weaken prematurely. An investigation revealed the root cause of the problem was due to a manufacturing defect in which the parts did not receive proper corrosion protection. My front subframe did not receive the proper corrosion protection. It's available for inspection. It's currently still at the dealership due to being unsafe to drive. I'm having steering issues while driving the vehicle when applying the breaks the vehicle pulls very hard to the left the whole car swerves to the left very dangerously. The problem has been reproduced or confirmed by a dealer or independent service center. The vehicle or component has Not been inspected by the manufacturer, police, insurance representatives. Only Dealer and independent service center did the inspection. No warning indicators no other symptoms, this issue took place around February - March of 2023. When I received the letter about the subframe recall I was excited thinking the issue would be fixed. But No it's unsafe

NHTSA ODI 11539978

Good morning. I previously reported incident [XXX] about a subframe issue w/ my 2011 Mercedes Benz C-300. This morning I received a warranty extension from the originally expired 4 years/50,000 mile to 20 years/unlimited miles. The notice says that repairs must be performed by an authorized Mercedes Benz dealership. I had the auto fixed privately and filed the NHTSA request. I called their CS and was told that I would need to visit a dealership, but to be honest I think that would be fruitless. Can MB be compelled to reimburse me for the cost incurred? Regards, [XXX] INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

NHTSA ODI 11517021

Like apparently the majority of this model year C300, the rear subframe is completely disintegrated. This is a known issue but Mercedes has not communicated it nor fixed it. I was told, and as the photos clearly indicate, this very likely could have resulted in a catastrophic or fatal accident as the entire rear is corroded. I have photo and video support as well as the inspection from a mechanic.

NHTSA ODI 11517129

The contact owned a 2011 Mercedes-Benz C300. The contact stated that upon entering the vehicle, he noticed that the inside of the vehicle was flooded with water. The contact then stated that he noticed that water had leaked from the sunroof and entered the cabin of the vehicle. The contact stated that several unknown warning lights were intermittently illuminated. The vehicle was taken to an independent mechanic where it was diagnosed that the wiring harness was severely damaged and could not be repaired. The dealer was not notified of the failure. The vehicle was not repaired. The vehicle was deemed a total loss by the insurance company. The manufacturer was notified of the failure and the contact was provided a case number. The failure mileage was 82,242.

NHTSA ODI 11514167

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

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

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

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

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

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

NHTSA ODI 11502449

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

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

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

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

Rusted left rear ear of rear subframe.

NHTSA ODI 11489990

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

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

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