2012 Mercedes-Benz C300 body & structure problems

Related recalls

No recalls on file.

What owners say

1. Filed Nov 24, 2025CTBody & StructureSuspension

   Mercedes of Danbury replaced the rear sub frame CODE 3441 47, since my mechanic (Newtown Auto Repair) told me that the Front subframe is in real bad shape, rotten/rusted, that it is dangerous to drive the car in this condition since the wheel and steering components are part and attached to it, the car would be out of control and all over the road any of these components fail and pull / brake away from the rusted out Sub Frame. When I brought the car in was under the…

   NHTSA complaint #11701264 · source
2. Filed Aug 20, 2025ILBody & StructureOther / Unknown

   Rear subframe rotted out and broke due to corrosion. Rear crossmember is broken and needs replaced. My safety as well as the safely of other was put at risk. Loss of control at high speed could have been deadly. Luckily, I wasn’t going very fast at the time of incident or else who knows what would have happened to me or bystanders. Independent service center inspected and confirmed that incident was due to corrosion in the rear. They informed me of the extended warranty (20…

   NHTSA complaint #11682005 · source
3. Filed Jul 8, 2024VABody & Structure

   We are having issues when braking. The backend of the car wiggles when braking hard. Shop advised that the subframe on the passenger side completely broke away and on the driver side it is very rotted. They advised this is a safety issue since the broken side could pierce the gas tank. I googled this and found that there was a warranty extension for the same year and make car (document MC-10233796-0001) Spoke to the service department and they advised this did not apply to…

   NHTSA complaint #11600131 · source
4. Filed Jun 4, 2024NJBody & StructureBrakesSuspension

   Took my car for a doorknob repair and was told the whole subframe is rotted. They told me not to drive the car on the highway. The car brakes very hard to the right and always goes right while making cranking noises. Car feels very unsafe. I paid a lot of money for this and own a 2012 c300 4matic.

   NHTSA complaint #11592433 · source
5. Filed May 18, 2024MABody & StructureBrakes

   This is a low mileage car with odometer reading of 25668 (less than 2000 miles per year), used sparingly and always parked in the garage. On 05/07/2024 I noticed brake fluid flowing from the left rear side of the car; on examination this seemed to come from the flexible hose that connects the brake fluid line to the brake caliper. I called my Mercedes-Benz (MB) dealer and arranged for further inspection and service. The technician identified that the brake fluid lines to the…

   NHTSA complaint #11589443 · source
6. Filed May 7, 2024143,000 miINBody & StructureSuspension

   The contact owns a 2012 Mercedes-Benz C300. The contact stated while driving at an undisclosed speed, he heard an abnormal sound coming from the rear of the vehicle, prompting him to pull to the shoulder of the roadway. After a visual inspection, the contact observed that both trailing arms had become detached. No warning lights were illuminated. The vehicle was taken to an independent mechanic, who determined that extensive frame corrosion had caused both trailing arms to…

   NHTSA complaint #11587466 · source
7. Filed Dec 21, 202395,000 miCABody & Structure

   The contact owns a 2012 Mercedes-Benz C300. The contact stated that the front driver's side interior door handle was fractured. The contact was unable to open the door from inside the vehicle. An independent mechanic inspected the vehicle and referred the contact to the manufacturer for assistance. The dealer was not notified of the failure. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for…

   NHTSA complaint #11561346 · source
8. Filed Jul 19, 2023110,000 miMABody & StructureBrakes

   The contact owns a 2012 Mercedes-Benz C300. The contact stated that the vehicle was making a loud bang sound towards the rear of the vehicle while driving over bumps in the roadway. The contact took the vehicle to the dealer and was informed that the rear subframe and the rear brake line were severely rusted. The subframe was replaced under an extended warranty coverage; however, the brake line was not covered under the extended warranty. The brake line was not replaced. The…

   NHTSA complaint #11533167 · source
9. Filed Jun 24, 2023NJBody & Structure

   Recently we had he brakes replaced and new tires put on to prepare for a trip out to Minnesota in a couple of weeks. My son felt like the car wasn’t driving correctly and took it to the shop and upon being put on the lift the service department called and said the rear subframe rusted out and was broken and the gas tank was scratched do to the subframe rubbing against it. When he called Mercedes they told him there was an extended warranty put on these cars which I never…

   NHTSA complaint #11528670 · source
10. Filed May 8, 2023120,000 miNYBody & StructureBrakes

    The contact owns a 2012 Mercedes-Benz C300. The contact stated that while his wife was driving at an undisclosed speed, she heard an abnormal sound coming from the rear of the vehicle. The vehicle was taken to an independent mechanic where it was diagnosed that the subframe wheel assembly needed to be replaced. No warning lights were illuminated. The vehicle was repaired; however, the contact stated that he received an unknown manufacturer’s recall for the subframe assembly…

    NHTSA complaint #11521006 · source
11. Filed Mar 3, 2023WABody & StructureSuspension

    The subframe assembly on my car is defective, as I learned today from my mechanic. This issue is known for my model of car and widely reported online. The mechanic says they have seen this issue before. I heard a strange noise while driving so I took the car to the shop after 60 days of enduring the sound. The shop immediately deemed the car unfit for driving and unsafe. In their words, if I had hit one bad pothole, the wheels could have come off the back of my car, and my…

    NHTSA complaint #11509955 · source
12. Filed Feb 27, 202395,000 miNYBody & Structure

    The contact owns a 2012 Mercedes-Benz C300. The contact stated that while driving approximately 55 MPH and pressing the brake pedal, the entire vehicle shifted to the left. Additionally, while driving at various speeds the vehicle was unstable and experienced vibration. The vehicle was taken to an independent mechanic who discovered that the subframe of the vehicle had severe rusting and corrosion and that the vehicle was unsafe to operate. The vehicle was not yet repaired.…

    NHTSA complaint #11509340 · source

Source: U.S. National Highway Traffic Safety Administration (NHTSA) Office of Defects Investigation public data. Complaints are submitted by owners and are not verified by NHTSA or by us; a complaint does not prove a defect exists. View this vehicle on NHTSA.gov Methodology