NHTSA Complaint #11427640 — 2011 MERCEDES-BENZ C300

On July 1, my daugther who is driving the car since about 8 months noticed a strange noise coming from the rear of the car. Since I was in Europe at that time I could not give her any assistance. On July 16 we both took a drive to Rhode Island to visit a college. I was the one driving, and I could also hear the noise coming from the rear. On the highway there was a back-up developing and I had to hit the brakes a littler harder. In doing so. the car was very unstable and it look like if the rear was going to overtake the front of the car. I was very scary even for myself who is a long time experience driver. After returning home I took the car to a mechanic and have him look at it. The resulting diagnosis revealed that the subframe was completely rusted out and was about to get disconnected from the under carriage of the car at any moment. The mechanic had a hard time to find a replacement part, and was finally able to locate an OEM subframe in California, the only one in the US. The price for the part alone was $1,500. I had no choice other than to have the car repaired at the mechanic since it was at that time undrivable. The total repair was almost $3,200. I took 2 pictures of the replaced subframe (see attached). The car is a 2011 MB C300-4-matic with just 100,800 miles on it. The was purchased used, with about 12,000 miles, in Febr. 2012 from Mercedes Benz of Westford, MA, which had used the car as a loaner/company car. The car was well maintained, used up until 2020 by my daughter's mother. She then bought herself another, newer C300 (2017 model) and decided to gift her older car to the daughter instead of trading it in. We thought, we knew a lot about the car and considered it a low risk transfer for a new, still learning driver. I will also file a formal complaint with Mercedes Benz if I have figured out the correct contact point. The internet shows, other people have experienced similar situations. And eventually, see also your ID-# 10504684 and 11023618.