Car was inspected by Mercedes Benz of St. Paul (MN). The rear subframe of the car was corroded (inside out) and the crossmember became disjointed from the rear subframe. I could have been in an accident while driving my C300 with a corroded out rear subframe. I was extremely lucky not to be in an accident while I was driving my C300 with a major defect like corroded rear subframe that caused crossmember to become disjointed from the rear subframe. I was lucky enough to avoid serious injury to myself and/or someone else if the rear subframe had collapsed due to unexpected corrosion. Mercedes Benz USA is aware of this defect since 2018 but they have not issued any recall. Since the rear subframe rusts out from inside, there will be no visible defect until the rear subframe fails.

- St. Paul, MN, USA

While driving noticed that the car was making a clunking noise from the right rear and car was not stable while making a turn and started to swerve to the right while braking. Jacked up the car this afternoon and see that one of the rear links rusted off from the rear subframe due to rust. Subframe is made of very thin metal that is not resistant to rust. Fortunately I didn't need to perform emergency braking since car is very difficult to control now. Car no longer drivable and needs a new rear subframe to be installed. ~ $5,000 dollars.

- Morristown, NJ, USA

The rear subframe is rusted and failing it is unsafe to drive. Mercedes is aware of the problem and has fixed the issue in Canada the UK and Germany free of charge. It would cost me around $4600 to fix out of my pocket. I have emailed the dealer where I take my car for service as well as corporate Mercedes in Germany and I am waiting for a reply. Why should I pay when they know it-€™s not safe and it-€™s a manufacturer defect " Are they waiting for a catastrophe before they recall"

- Galloway, NJ, USA

Failure of rear subframe at passenger side connection to the lower thrust arm/trailing link that transmits force from wheel carrier to car frame. The bracket portion of the rear subframe for this connection tore loose at the weld to the carrier, possibly during moderate acceleration at an at-grade railroad crossing in downtown St Paul, MN. This occurred on 8/12/21 at roughly 4:15 in the afternoon. The car became difficult to drive and control, requiring the steering wheel to be turned slightly to the right and held there while the car was going straight. The dealership was contacted about the failed subframe but neither they nor the OEM has inspected the vehicle.

- St Paul, MN, USA

Stepped on the brakes and the car veered sharply to the right. Vehicle felt very unstable. Would of been horrible if the surface was snow covered or icy. Took into a repair facility and found out the rear subframe has rusted to the point of failure. The rear tire could move several inches. Somebody could be killed or severely injured.

- West Salem, WI, USA

On July 2, 2020 had a brake job done. While doing brake job it was noticed that the rear sub frame was completely broken free from the front mounting bolts on both sides ( leaving only the 2 rear mount bolts to hold the entire subframe, differential, axles, rotors, calipers, and rear wheels). Called Mercedes usa to ask about warranty claim and they said no. This sub frame was broken in the exact same spot on both sides. I would think that this issue is a part defect, or an engineering design fault. Mercedes should be responsible for the repair of this condition which is extremely unsafe.

- Troy, OH, USA

I work at a Mercedes dealership and we are starting to see the rear cradles rusting completely out, cause strut links to come loose from the cradle causing brake and drivability problems, this is a very unsafe problem that needs to be addressed by mbusa, to this date we have had 5 cars with this condition in the last 6 month or

- Marietta, OH, USA

Front suspension dropped to low and hits the tires while driving car causing flat to tire and lose control of car very dangerous.

- Homestead, FL, USA

When driving on the freeway at a certain speed the rear end starts fishtailing making it hard to control the vehicle

- Houston, TX, USA