*Median odometer reading when the problem happened, where owners gave one. One complaint can name several problem areas.
Engine
Hi, in the Fall of 2025 my 2016 Mercedes Benz C300 4 Matic, started giving off smelly fumes while my car was idling/ warming up. I registered a complaint with the Corporate Mercedes Benz Office USA, LLC in April 2026 @ 800-367-6372, after the dealership would not correct the issue free of charge. 1. Hose Clamp Replacement problems. 2. The raw fuel leakage produces strong gasoline odors inside the cabin- via the air filter, risk of car stalling and the smell could be leathal. 3. The problem was confirmed in a lawsuit. 4. The dealership would not repair the issue. 5. There were no warning lamps or messages on the dash board, the only essential issue were the smells, fumes, odors and lawsuit.
Oct 15, 2025Suspension
Vehicle: 2016 Mercedes-Benz C300, VIN [XXX], approximately 52014 miles. Purchased Certified Pre-Owned in 2017. All maintenance performed at authorized Mercedes-Benz dealerships. On XXX, during a routine B-Service at Mercedes-Benz of Easton ([XXX]), the technician found that the rear subframe (rear axle carrier) was rusted and perforated. The corroded area is located directly above the rear control arm. The technician stated on a recorded inspection video that the corrosion would continue to spread around that area until the control arm disconnects, and described it as a safety hazard. He recommended replacement of the part. Photos and video (technician shared video link - [XXX]) were taken…
Oct 24, 2026Structure › Body
Rear sub frame has rusted through and according to repair shop cannot be safely driven until repaired. Mercedes has granted extended warranty for sub frame rust through for the C300 up to model year 2015 so this is a known problem. My car is a 2016 and Mercedes will not offer the extended warranty.
Oct 9, 2026Suspension
Failed state safety inspection due to a severely corroded and rotted rear subframe, creating an immediate driving hazard.
Oct 5, 2026Structure
The contact owns a 2016 Mercedes-Benz C 300. The contact stated that while performing maintenance on the vehicle with the dealer, it was discovered that the rear subframe was severely rusted and perforated. The contact associated the failure with Technical Service Bulletin: MC-10232321-0001; extended warranty, but vehicle was not included. The manufacturer was contacted by phone and made aware of the failure. The failure mileage was approximately 84,616.
Sep 2, 2026 · 84,616 milesUnknown or other
Vehicle has prematurely rusted subframe. It is a know manufacturer defect, for which the manufacturer is covering repair cost for owners of the preceding model, but refuses to acknowledge responsibility on this model. (W204 model covered â W205 Mercedes (only offered $500.00 on a repair they value at over $6,000.00.))
Aug 5, 2026Engine
NHTSA Safety Complaint â 2016 Mercedes-Benz C300 Vehicle: 2016 Mercedes-Benz C300 | Mileage: 74,662 miles What Happened Iâm filing this complaint because my 2016 Mercedes-Benz C300 suffered a sudden, complete engine failure at 74,662 miles, and I believe itâs a safety risk that deserves investigation. Iâve owned this car since 2016 and followed every recommended service interval. All available warranties were purchased and maintained. The car showed absolutely no signs of trouble before this happened. Last week before filing, I was driving normally when the check engine light came on without any prior warning â no oil pressure light, no temperature alert, nothing else. Within…
May 11, 2026Fuel/propulsion system
Iâve been driving my car since September when it was purchased I just got it from dealership 4/9/26 spent over $1100 and have been working like regular full time schedule, I wake up today 4/27/26 trying to work and car is stalling. Not sure whatâs going on with these mechanics and technicians. I pay to dollar to ensure my family safety on the road here I am stuck without support due to my circumstances. Also, my car just idles the shuts off doesnât turn mall the way on, magically a check engine light flashed then car just immediately stalled and wonât turn back over all the way.
Apr 27, 2026
Owner complaints are submitted to NHTSA by the public and are not verified. Shown as filed (NHTSA removes personal details); long reports are shortened.