Mercedes-Benz C300 Structure Problems
Owners have filed 380 complaints with NHTSA about structure problems on the Mercedes-Benz C300 across 17 model years. The 2015 model year has the most (60). The words owners use most often: “rear subframe” (28% of reports).
- 380structure complaints
- —median miles at failure
- 10mention a crash
- 11mention an injury
- 3related recalls
- $2,850typical repair cost reported by owners
- 60%of reports with a speed happened at 50+ mph
What owners describe
Phrases that appear unusually often in these complaints compared with complaints about other cars.
- Rear subframe: mentioned in 107 of 380 complaints (28%)
- Sub frame: mentioned in 33 of 380 complaints (9%)
- Panoramic sunroof: mentioned in 25 of 380 complaints (7%)
- Door handle: mentioned in 22 of 380 complaints (6%)
How much does it cost to fix?
Owners who wrote down what they paid or were quoted put the typical structure repair on the Mercedes-Benz C300 at $2,850, and half of them between $1,500 and $5,700.
Based on 27 NHTSA complaints about this problem alone that state a repair bill or quote (2015–2025), converted to 2026 dollars with the U.S. consumer price index. These are owners' own figures, not a quote: they include dealer quotes, and owners who file complaints often faced larger repairs, so they can run higher than typical shop prices. Prices vary by shop, region and warranty coverage. How we calculate this.
At what mileage do structure problems happen?
Based on 175 complaints that reported the odometer reading.
How serious are the reports?
Of 380 complaints, 10 mention a crash, 1 a fire, 11 an injury.
Mercedes-Benz C300 structure complaints by model year
| Model year | Structure complaints | Share of that year | Median miles |
|---|---|---|---|
| 2026 C300 | 1 | 50% | 1,729 |
| 2025 C300 | 1 | 25% | — |
| 2023 C300 | 1 | 5% | — |
| 2022 C300 | 1 | 4% | 6,000 |
| 2020 C300 | 4 | 12% | 28,722 |
| 2019 C300 | 7 | 10% | 48,000 |
| 2018 C300 | 14 | 14% | 47,000 |
| 2017 C300 | 24 | 11% | 40,000 |
| 2016 C300 | 27 | 9% | 45,000 |
| 2015 C300 | 60 | 16% | 62,612 |
| 2014 C300 | 9 | 10% | 51,500 |
| 2013 C300 | 58 | 22% | 80,000 |
| 2012 C300 | 54 | 20% | 110,000 |
| 2011 C300 | 49 | 10% | 105,000 |
| 2010 C300 | 34 | 8% | 63,000 |
| 2009 C300 | 27 | 5% | 92,100 |
| 2008 C300 | 9 | 1% | 66,000 |
When owners reported it
Related recalls (3)
Structure:body:roof and pillars
Model years: 2015, 2016, 2017, 2018, 2019, 2020
Problem: Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2014-2020 C-Class, CLA, GLA, S-Class, GLC, and GLE vehicles. Please refer to MBUSA's recall report for specific vehicle details. The front roof panel located between the windshield and the panoramic sunroof may not have been bonded correctly to the vehicle during a prior repair, allowing the front panel to detach from the vehicle.
Risk: A detached roof panel can become a road hazard, increasing the risk of a crash.
Fix: Dealers will replace the front panel, free of charge. Owner notification letters were mailed on August 2, 2024. Owner notification letters will be mailed in phases, on, March 22,2024, and August 2, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. This recall is an expansion of NHTSA recall number 21V-197.
Structure:body:roof and pillars
Model years: 2015, 2016, 2017, 2018, 2019, 2020
Problem: Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2020 C300 Coupe, C43 Coupe AMG, C43 AMG, 2015-2020 C300, GLA250, 2016-2018 C350e, CLA45 Coupe AMG, 2015 C400, S65 AMG, 2015-2019 C63 AMG, 2016 C450, 2015-2016 GLA45 AMG, S600, 2016-2020 GLC300, 2017-2019 GLC43 AMG, GLE43 Coupe AMG, 2014-2019 CLA250 Coupe, 2014-2015 CLA45 AMG, 2018 GLC63 AMG, 2014-2017 S550, 2018-2020 S450, 2016-2019 GLE63 Coupe AMG, 2016 GLE450 Coupe, 2014-2020 S63 AMG, 2018-2019 S560, and 2019 GLC350e vehicles equipped with a panoramic sunroof. The front roof panel located between the windshield and the panoramic sunroof may not have been bonded correctly to the vehicle during a prior repair.
Risk: The adhesive bonding of the front panel might deteriorate, possibly causing the front panel to detach from the vehicle and become a road hazard, increasing the risk of a crash.
Fix: Mercedes-Benz dealer will remove the bonded panel and will install a new front panel by following the detailed repair instructions and using the approved primer, cleaner and adhesive, free of charge. Owner notification letters were mailed on September 3, 2021 and October 26, 2021. Owners may contact MBUSA customer service at 1-800-367-6372.
Structure:body
Model years: 2017, 2018
Problem: Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2018 Mercedes C300 Cabriolet, C300 4Matic Cabriolet, C43 AMG Cabriolet, C63S AMG Cabriolet, and C63 AMG Cabriolet vehicles. Due to a bonding issue introduced in the production process, the rear beltline trim may separate from the vehicle.
Risk: If the beltline trim were to separate from the vehicle while driving, it could become a road hazard, increasing the risk of a crash.
Fix: MBUSA will notify owners, and dealers will inspect the rear beltline trim and replace the trim if necessary, free of charge. The recall began on September 21, 2018. Owners may contact MBUSA customer service at 1-800-367-6372.
What owners report
Short excerpts of recent complaints, with personal details removed. Full reports are on NHTSA.gov.
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…
The contact owns a 2015 Mercedes-Benz C300. The contact stated that while driving at an undisclosed speed, there was an abnormal sound coming from the vehicle and the vehicle became difficult to maneuver. The failure had occurred on several occasions. The vehicle was taken to an independent…
The contact owns a 2026 Mercedes-Benz C300. The contact stated that there was white powder discovered inside the vehicle. The contact initially thought that it was mold. The contact stated that the heating system had caused the issue. The air bag dust was on the headliner and the driver's side…
Front roof panel came detached at hwy speed
The contact owns a 2015 Mercedes-Benz C300. While the contactâs son was driving approximately 20 MPH, the vehicle veered to the left and into the next lane when the brake pedal was depressed. The vehicle was cautiously driven back to the residence and parked. The vehicle was later towed to the…
Frequently asked questions
Do all Mercedes-Benz C300s have structure problems?
No. NHTSA has 380 owner complaints about structure for the Mercedes-Benz C300. Complaint data shows that the problem is reported, not how many of all cars sold are affected.
Was there a recall on the Mercedes-Benz C300 structure?
Yes: 3 safety recalls list structure. Check your VIN on NHTSA.gov to see whether the fix was done on your car.
How much does it cost to fix structure problems on the Mercedes-Benz C300?
Owners report a typical cost of $2,850 (half paid between $1,500 and $5,700), from 27 complaints that state a repair bill or quote, in 2026 dollars.
What do owners say about structure problems on the Mercedes-Benz C300?
The most frequent phrase is “rear subframe”, in 107 of 380 complaints, followed by “sub frame” (33).
Other Mercedes-Benz C300 problems
- Air Bags problems (1,213)
- Electrical System problems (750)
- Steering problems (493)
- Engine problems (455)
- Exterior Lighting problems (310)
- Suspension problems (307)
- Fuel/propulsion System problems (261)
- Power Train problems (119)
See all Mercedes-Benz C300 problems.