2012 Mercedes-Benz C-Class Suspension

The contact owns a 2012 Mercedes Benz C300. The contact stated that while driving at various speeds, the vehicle would shake without warning. The vehicle was taken to an independent mechanic for a tire rotation; while there, the mechanic discovered severe corrosion on the vehicle's subframe and the contact was advised to no longer drive the vehicle. The manufacturer was notified of the failure. The vehicle had yet to be repaired. The failure mileage was approximately 160,000. The VIN was not available.

Rear subframe crossmember rotting, needs replacement. It seems to be a common problem with this vehicle and the assumption by most professional is that it a faulty part supplied by a third party to Mercedes. The rest of the cars undercarriage is pristine, making me wonder why just this one part would rust out.

Took the car in for an oil change and asked them to look at the brakes and rear as there was a strange noise. Vehicle was inspected and found the entire subframe is rotted. Was advised this is a common problem with Mercedes and there were some recalls. Unfortunately no open recall on this vehicle and it is now not driveable as this is a safety risk. Car has been driven 60 miles/day for the past 3 months and could have had serious consequences.

Subframe rusted and broke. It is available for inspection. Burlington Mercedes inspected the vehicle and told me it was not safe to drive. Mercedes-Benz USA is aware of the problem. They issued a letter extending the warranty covering only the subframe to twenty years and unlimited miles. Burlington Mercedes refused to do the subframe replacement without installing all new arms, which are currently not damaged. The cost to install all new arms is $2826.54. Mercedes-Benz USA is offering a warranty extension that their dealerships refuse to honor. This needs to be turned into a recall instead of a warranty extension. This subframe issue is dangerous. It affects Mercedes vehicles dating back to 2005 and encompasses many of their models including: SLK- Class, CLS-Class, SL-Class C-Class Sedan/Coupe, GLK-Class E-Class Sedan/Wagon, E-Class Coupe/Cabrio

the rear subframe broke while in motion and caused the car to drift and bounce while i was cornering the traction control and stability control intervened and i also counter steered once back in straight line i braked and the car tilted on the side, we lifted the car in a mechanic shop and found a rotten subframe one side broke the other was almost giving up.

a rusted rear subframe is more prone to crack when a driver hits a pothole or wants to brake quickly, which can lead to instability in the vehicle's rear suspension.

The rear subframe rusted prematurely and broke off important mounts for the suspension and steering. I was driving and had to hard brake. This cause the back end of the car to swerve and almost lose control. I then heard a knocking sound when I pressed the brakes, prompting me to take it into the shop. There I was informed the the subframe was rusted and the vehicle wasn’t safe to drive. I filed a claim with my insurance, but they said it’s wear and tear.

Failure of rear subframe causes car to lose control. Only found out about the problem after I received a Mercedes extended Warranty in mail March 2023, roughly 6 months after OEM Undercarriage failed and forced me to purchase another Undercarriage in cash/no insurance involved because part back ordered for many months. Car thus inoperable for roughly 4 months. At moment of the OEM failure, total loss of control. Mercedes refuses to reimburse for cost of replacing undercarriage regardless of the fact that failure occurred before notification and regardless of fact that part unavailable for months

I was driving on the freeway and had to hard brake due to unexpected stopped traffic. When I braked the vehicle veered hard to the left and almost lost complete control of the car and nearly caused a serious accident. I drove immediately to a local MB dealer and they confirmed what I was afraid and suspected which was the right rear subframe needs replaced. This car was recently sold to me by a dealer less than a month ago and not a single warning light or indicator warning me of this issue. The repair is over 7500 and the shop highly recommended I no longer drive until it’s replaced. This problem is very common and MB actually covers the cost in Europe and Canada.

During planned car service my mechanics discovered that rear subframe is broken and is not safe to drive anymore. After investigation I found that this is a major issue that Mercedes owners have with this particular model. In Europe for this issue has been issued Recall, however in US for some reason Mercedes don't take responsibility. This is a major Safety hazard with possible fatal consequences.

A problem with the rear subframe had occurred in which it had started to rust. Due to the severity of the issue I noticed my car started veering when hitting the brakes as well multiple concerning sounds and stability issues with the vehicle. Mercedes has not contacted me about replacing the part nor has their been any warning lights or any indication of the issue being present other than when the subframe had already been rotted. When speaking to MB about the issue their was nothing they could do for me which is questionable being that the cause of this is a manufacturing issue. I have yet to receive any information as to how the issue may be resolved. Not only does this put myself at my family at risk but as well as the community around me. Wether when braking my vehicle may veer and cause a collision or an issue where the subframe fails and causes an accident.

The left side of rear subframe has rusted out. The right side had been repaired by welding by a previous owner. The damage is still present and can be inspected. The broken bracket is right next to the gas tank and can possibly contact or dent the tank during a hard break or collision. This is a common problem with many people expressing this online and at the 3rd party repair shops. No warning signs were present until the bracket snapped. Extensive rust and corrosion around the area, specifically on the inside of the subframe.

Issue with my rear sub frame rotting out due to rust almost causing a very bad accident in a hard braking situation

My vehicle had started swerving when I had hit the brake. I noticed that my rear subframe had been rotting and did more research only to find that this was a common problem amongst Mercedes Benz owners. This is a huge safety issue as not only does it put my cars entire suspension at risk and cause a life threatening accident to me or others on the road it is also very concerning when my vehicle creaks and makes constant noises when driving. There are times it feels as if my vehicle’s suspension will fall out from under it and has been a clear issue Mercedes is aware of yet I have not received any recall notice nor have I gotten any answer as to how Mercedes can help me fix an issue they continuously overlook and sweep under the rug. I fear that eventually something will happen and have been trying to get an answer as to how to get my vehicle repaired without it coming back on me since the root of the issue lies in MBUSA parts snd not on my own doing.

I was driving our Mercedes Benz C300 and noticed the braking distance taking longer than normal. Also, the rear end responding differently than normal. We took our Mercedes C300 to Mercedes Benz Dealer to be serviced. The technician looked under the car and found the rear subframe rotted out. The service advisor informed us of this being a known defect. We have to be cautious about driving the car until it's repaired due to the fact of being a serious safety issue. MB needs to recall these vehicles and repair them before someone is seriously injured in an accident. Many drivers are uware their subframe has rotted out. I've taken this car to the same MB shop for 8 years and all in a sudden this comes out of nowhere.

So here I am - another "happy" driver with a rotten subframe. Started noticing instability on the highway speeds a few months ago. Cracking noises lately. Since I use this car my very honest mechanic immediately told me that my rear subframe is completely done and I should not be driving the car until it is replaced. He quoted me $4500 (OEM parts + labor), but suggested that I take my car to MB and insist on covering the repair costs as this issue did not seem typical to him at all. I started googling and ended up here. Seems like this is a common issue and sounds like MB will replace the subframe for free in some other countries (cananda and Germany, .The dealer said the repair will cost Over $5000.00 This is a safety issue, A real big one. And the fact it's covered in other countries is so not fair. I own another mercedes and now I feel the cars are not as safe as they used to be. Please let me know what I need to do next

I went to my dealership for a routine yearly service appointment, which I do regularly, along with yearly inspections. My car was purchased new to my liking in 2012 with input from my late partner who passed before I received it! I waited quite some time to get my gem. When it arrived, I had all I could do to drive it, given my loss. I garage it every day for the last 10+ years, never left it outside, it is pristine, only has 64,000 miles on it. To my disbelief, was informed by the MB technician yesterday that I have corrosion on my left rear sub panel, and that I should not drive it and consider a trade-in - NO WAY!! And that the part would cost me over $4,800 to replace and it would not be available until February 2023. So, I should drive another car, which I do not have!!!!! After researching, I am beyond disappointed that this is a known MB manufacturer's defect that has gone this far, customer action needs to be taken!!! My local car dealership states they knew nothing about this, however; pointed out a number of Mercedes C300 in their parking lot sitting with the same life-threatening issue. They were eager for me to talk to sales for a trade-in. Go figure this strategy, NOT. I have had three Mercedes Benz which I love, I do not want to part with this gem, but my need to . . . Please do something . . . Safety and Life matters

The contact owns a 2012 Mercedes-Benz C300. The contact stated that upon parking the vehicle at the dealer parking lot, she heard abnormal sounds coming from the rear of the vehicle. There was no warning light illuminated. The dealer diagnosed that the rear subframe was severely corroded and the rear control arm was detaching from the subframe. The dealer diagnosed that the subframe needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline. The failure mileage was approximately 79,000. The contact was informed by the service advisor that the vehicle should not be driven until it is repaired due to the extensive damage to the subframe.

Diagnosed with broken rear sub frame: "Broken rear sub frame, left side lower link is broken off and contacting Fuel Tank. Rear tires are also bald and care is unsafe to drive". Recall in Canada, but not USA. Sub frames on backorder until January 2023. I have three years of payment left, and am now being quoted 6,300 from the MB Service Ctr in Wilmington DE to fix this problem. Again, the items are on backorder due to heavy demand. Im a single mom we depend on my car to get us to work. This is the ultimate catch 22 as the car is extremely dangerous to drive and put us all in serious jeopardy - but no one will take this broken car as a trade in. I am forced to drive the vehicle while I wait for backordered parts and pray that I can get a loan to pay for it. "".....and contacting the fuel tank".....

The contact owns a 2012 Mercedes-Benz C300. The contact stated while driving 25 MPH going downhill, the rear end of the vehicle shifted independently to the right. The contact stated no warning light was illuminated. The contact was able to continue driving at a slow speed to her destination. The contact stated her husband inspected the vehicle and became aware that the rear subframe cross member had fractured due to corrosion. The vehicle was not diagnosed or repaired. A dealer was not contacted. The manufacturer had been informed of the failure. The failure mileage was approximately 149,000.

Subframe corroded/rusted out. Car is in excellent condition with no other rust or corrosion. Car has 58,800 miles and regularly maintained by dealer. Took car to TireDiscounter because of noise. Mechanic put car on lift and reviewed corrosion and other damaged cause by failed part. Mechanic called MB service department and was told that parts on 5- 6 months back order because of this issue. But no recall even though problem is wide spread. Rear tires and gas tanked damaged by loose subframe.

Major rust in the welded joints of the Steel subframe. Long crack development along the seams, could have led to catastrophic lost of control of vehicle if the breaks were not found. This is an apparent flaw with the C-Class Mercedes Benz and quite surprising to the Service Reps at my dealership that this has not been a recall issue, as they’ve replaced many. The repair is quite costly, over $5,000. There were no symptoms, warnings or messages. This was found when the vehicle was in for a 10k service. I have a video sent by the technician that show the inspection of the vehicle.

I ran off the road and my rear suspension sub frame literally broke in half. Upon further research I’ve learned that these parts are faulty and several people have had theirs rust completely in two. Mine had lots of rust damage and that is likely what caused the damage to mine when I ran off the road (MINOR impact that should have never caused that much damage). Mercedes has recalled this part in several countries including Germany and Canada. When I drove home after running off the road my car was nearly impossible to drive. It was jerking all over the road and when I tapped the brakes the rear end of the car would come up off of the road (into the air)! This was in June. It’s now September and I still have not been able to obtain a part from Mercedes. So many people are having this issue with their vehicles that the part is on back order until Q1 of 2023. This is a part of the cars sub frame that is rusting in two! One would argue a broken sub frame is dangerous. And it’s such a prominent issue the part is on back order. Furthermore, Mercedes has changed the type of metal used in replacement parts, which is an acknowledgment of the parts defect.

Corroded rear cradle driver side. Causing instability driving. Cradle on back order for months according to local Mercedes parts department

The rear sub frame has rusted out and broken causing the car to veer suddenly to the left during braking. A quick search of the internet reveals that this is a common problem with this car. The dealership has quoted me $4,000 for the repairs.