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

the rear subframe rotted away

NHTSA ODI 11488118

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

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

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 am reporting a big safety hazard issue on these Mercedes C300 model year 2011. The suspense bracket just breaking off with obvious no visible issues. The suspension support bracket is got rotted with rust from inside out and broke off while driving on the highway. The issue was obvious when I braked suddenly and the car just pulled itself to the right side. This could easily cause an accident. I reported the incident to Mercedes and they told me to report to NHSTA and they cannot do anything. Once home and jacked up the vehicle I found that the bracket was completely off the frames and it did hit the gas tank causing a dent in the tank (a big safety issue) seam. I googled the issue and it seems like it is a known issue with these models and Mercedes have not recalled or fixed this issue on any vehicle. I have attached pictures of the broken bracket. Thank you

NHTSA ODI 11480326

1. Rear Subframe of the car rusted out, causing car to suddenly jerk to the right while braking. as inspected by my mechanic, the driver side part of the rear subframe is also about to fail as well 2. The sudden jerky movement can probably cause me to lose control and possibly crash into another vehicle, potential hurt myself and other cars around me 3. Yes, the problem has been reproduced and confirmed by an independent service center 4. The vehicle or component has not been inspected by the manufacture, police, insurance representatives. It's only been inspected by my mechanice. 5. No warning lamps or symptoms appeared prior to subframe failure

NHTSA ODI 11476064

I took the car to Mercedes for service and they found that the rear suspension frame had extensive rust and recommended that it should be replaced. The car only has 87,000 has been garage kept since buying the car in 2013 and has been serviced my MB. The frame has two quarter size holes at the same location on the left and right sides. MB was made to recall this in both Canada and Europe. MB stated that this is a known issue with this car. Why has the NHTSA not forced MB to recall this car? MB knows that if part fails the entire rear drivetrain separates from the car. My understanding is this effects most C-class E-class cars, plus the repair is over $4,000.00 This should be on MB not the consumer.

NHTSA ODI 11472904

The car started fishtailing slightly when the brakes were applied at speeds around 25 MPH. First it was taken to a Mercedes dealership on June 24th where they said it need a sway bar and tires. They were not sure that would address the issue. When we went to get tires, the tire person said the control arm was connected to nothing in the rear. The rear subframe was rotted to the point that there was not a place to even weld it back on to and needed to be entirely replaced. The fact that Mercedes missed it is shocking in itself, I can only assume (we bought the car used) it was rotted from use in winter weather before we got it. The repairs have been estimated to cost between $2200-3800-.

NHTSA ODI 11472916

The contact owns a 2011 Mercedes Benz C300. The contact stated while driving 35 MPH, the brake pedal was depressed abruptly and the vehicle fishtailed off the road. The contact stated no warning light was illuminated. The contact was able to continue driving to her destination. The contact took the vehicle to an independent mechanic and was informed that the brake calipers needed to be replaced. The vehicle was not repaired. The contact called the local dealer and made them aware of the failure. The contact continued to experience the failure. The contact took the vehicle back to the independent mechanic and was informed that the subframe was corroded. The vehicle was not repaired. The manufacturer had not been informed of the failure. The failure mileage was approximately 160,000.

NHTSA ODI 11471990

I noticed that when using the brakes the car would pull to the side. The front brake rotors and pads were completely replaced but the pulling behavior remained unchanged. When the mechanic specifically looked for reasons for the pulling he found the rear driver's side stabilizer completely rusted through and the passenger side one showing signs of similar impending failure. I took pictures of both. The driver's side arm that was broken was also rubbing against the gas tank. The company, Mercedes, is only allowing replacement parts to be delivered when ordered by VIN, so I can't get a part already in the US (it has to be ordered directly from Germany and specifically for my car's VIN - they KNOW there's a problem).

NHTSA ODI 11465799

I have a 2011 C300 Sport that I purchased end of the lease (3yr.). The car was never driven in the winter for 4 seasons and most recently just the last 3 winters. Complete frame rot on the rear driver's side. Rot was noticed by my mechanic at the last oil change. He said he is replacing three rear frames for customers as soon as he can get parts. Parts are limited and only in Germany. I want it repaired with genuine parts. If the frame separates while the vehicle is at highway speeds, operator control can be compromised. The brake line which attaches to the frame has ruptured in many cases from what I have read. I called MB customer service and there is no recall at this time. I called the local dealer and they have been replacing quite a few frames with the same issue. This is a dangerous failure and if I remeber correctly about 8-10 years ago Toyota recalled trucks and SUVs for frame replacement.

NHTSA ODI 11464212

Due to design flaw and/or poor material quality, I have a car with less than 100,000 miles that has completely rusted thru the subframe. I was told by a Mercedes Benz dealer that this is a common problem with this car. The cost of repair was quoted at $4000. This was only discovered due to the MB mechanic removing the covers on on the subframe discovering the rust. I was told it would not pass inspection but it just did in February at the dealer I bought the car from. I told the MB dealer this and they said they probably didnt know the covers need removed to see the issue. This is a huge safety issue that people who drive these cars are probably not aware of. Failure of this area could cause loss of control as this is a critical suspension link responsible for maintaining steering direction of the rear wheels. Once these linkages fail the driver will lose control of the car. MB needs to held accountable for this design flaw and get the cars recalled. I do not have $4000 just lying around to make this repair and will be forced to continue to drive this car.

NHTSA ODI 11461106

While traveling on the interstate @ 60 MPH, I loud knock was heard in the right rear. When brakes were applied, the vehicle pulled to the left, severely. Vehicle was taken to a mechanic on this date after making an appointment. Photos included show the issue as to why this occurred. The 'cradle' of the rear suspension on both, the left and right sides were completely rusted through. The vehicle is a 2011 Mercedes-Benz C-300, with 63,000 miles. After researching this on line, it appears this is an on-going issue with this year along with other years. This, is huge safety issue and the results could be catastrophic to the occupants and or other operators.

NHTSA ODI 11457695

The rear suspension subframe rotted. The car has 140,000 miles and is kept in a garage. There was no warning regarding the damage. I nearly lost control of my car on a highway, it was I reported this to Mercedes to see if there was a recall. There was no recall on the part, Mercedes did not take responsibility for repairs. I paid to have the car repaired. There were no warning lamps that alerted me to the problem. The car was towed to a Mercedes dealer and I opened a claim with Mercedes.

NHTSA ODI 11452412

The contact owns a 2011 Mercedes-Benz C300. The contact son stated while driving at various speeds, the rear of the vehicle would sway while braking. The contact stated no warning light was illuminated. The vehicle was taken to an independent mechanic and was diagnosed with needing the subframe to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure and informed the contact that to take the vehicle to an authorized dealer for assistance. The failure mileage was approximately 119,000.

NHTSA ODI 11443670

Rear subframe failure of left lower control arm mount bracket at weld that rusts prematurely from improper treatment at time of manufacturing After failure while braking at low speed 10mph rear end of vehicle fish tails left and front end of vehicle moves right There are numerous reports around the world with this specific model and identical safety hazard on the left side of vehicle in almost all cases Mercedes Benz refuses to acknowledge a defect in craftsmanship of the specified part and in many cases offer a $1000 credit towards a new vehicle As 1 of millions of Americans that owns this vehicle in question I believe it is necessary that the NHTSA steps in to assist with this issue as millions of American lives are at risk even if they do not own or operate this vehicle

NHTSA ODI 11443558

Lost control of vehicle while driving on highway. Brought vehicle to have brakes done at Pep Boys who identify the sub frame was corroded and that vehicle was not drivable, after many attempts with Mercedes Benz, from emails to phone calls also following up with customer service line and not been able to even have them look at the vehicle I’ve decided to follow up with a complaint. My car was earlier this year at Mercedes-Benz for another reason and I was never made aware of this issue. I brought vehicle to another European auto shop they just told me that they just did another vehicle same model with same problem. I’ve also read online many complaints. I’m aware that many individuals have no idea on how to file a complaint at this level to hold MBenz responsible. Is time for a recall. My extended warranty company would not take care of the bill which is over $2000 since there is corrosion on the vehicle. Thank you for your assistance

NHTSA ODI 11440684

Rear suspension is rusted and the arm to the wheel has disconnected. This vehicle can’t be driven and is a major safety issue - per the Mercedes dealership. From Mercedes : The rear sub-frame serves a number of purposes. It adds to the rigidity of the rear body structure and supports the vehicle's cabin and some chassis components. Most importantly, the sub-frame helps to protect occupants in an offset rear impact. In a collision, the sub-frame first helps to absorb some of the impact forces on the side that is hit. It also channels some of the impact forces to the side of the vehicle not involved in the impact. This also helps to absorb some of the forces of the collision before they can reach the passenger cabin Reason A damaged sub frame puts everyone in the vehicle at risk. During a collision the sub-frame is responsible for absorbing and evenly distributing the force from the impact. If damaged the sub frame cannot distribute the impact causing a complete collapse of the vehicle.

NHTSA ODI 11435150

The contact owns a 2011 Mercedes-Benz C300. The contact stated while driving 25 MPH, the contact was going around a corner when he noticed a vehicle in front. The contact depressed on the brake pedal and the vehicle violently jerked and stop. The contact stated that the steering wheel was leaning towards the left. The contact was able to drive the vehicle to his residence. The following day the contact took the vehicle to an independent mechanic who inspected the vehicle and diagnosed the failure as a fractured and detached rear control arm due to corrosion of the undercarriage and subframe. The vehicle was towed to a local dealer to be repaired however, the contact declined the repair due to cost. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 82,000.

NHTSA ODI 11432823