YearToAvoid

2018 Mercedes-Benz C300 Structure & Body Problems

Structure & Body complaints account for 15 of 99 total complaints (15%) filed for the 2018 Mercedes-Benz C300. NHTSA lists 5 related recalls covering the front roof panel, rear beltline trim, and seatback locks. Median mileage at failure is 49,000 miles, with 2 crashes and no fires reported.

Structure & Body complaints
15
15% of 99
Crashes reported
2
Fires reported
0
Injuries reported
0
Median mileage
49,000 mi
Related recalls
5

Typical body and structure symptoms owners report

  • Front roof panel separates or detaches from the vehicle while driving at highway speed, in some cases striking the rear of the car.
  • Panoramic roof glass shifts or partially detaches from its mounting, allowing water to leak into the cabin.
  • Bonding agent on the front roof panel between the sunroof and windshield fails, causing interior flaking, cracking, and lifting.
  • Adhesive holding the rear window to the convertible top detaches, letting water seep into the interior.
  • Front passenger side fender becomes partially detached from the body on a low-mileage vehicle.
  • Owners report recall parts for the front panel repair were unavailable for weeks after notification.

When 2018 Mercedes-Benz C300 body and structure complaints were filed

First complaint Jun 19, 2018, latest Sep 16, 2026.

2018 Mercedes-Benz C300 structure & body complaints: complaints filed per month2Jun 2018Sep 2018Jan 2023May 2024Sep 2024Aug 2025Aug 2026
15 complaints filed with NHTSA from Jun 2018 to Sep 2026; peak May 2024 (2).

Structure & Body recalls for the 2018 Mercedes-Benz C300

  1. NHTSA 23V854000Dec 15, 2023Structure & Body2,976 vehicles

    Structure:body:roof and pillars

    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.

    Remedy: 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.

  2. NHTSA 21V197000Mar 19, 2021Structure & Body15,096 vehicles

    Structure:body:roof and pillars

    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.

    Remedy: 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.

  3. NHTSA 19V130000Feb 26, 2019Structure & Body22,637 vehicles

    Seats

    Mercedes-Benz USA, LLC (Mercedes) is recalling certain 2017-2018 Mercedes-Benz C300 Cabriolet, C300 Coupe, AMG C43 Coupe, C300 4MATIC Cabriolet, C300 4MATIC Coupe, AMG C43 Cabriolet, AMG C63 Cabriolet, AMG C63 Coupe, AMG C63 S Cabriolet and AMG C63 S Coupe vehicles and 2018 Mercedes-Benz E400 Coupe, E400 Cabriolet, E400 4MATIC Cabriolet and E400 4MATIC Coupe vehicles. The seatbacks of the front seats may not properly lock on the right side of the seat.

    Risk: If the seatback does not properly lock, in the event of a crash, the seatbacks may fold forward, increasing the risk of injury.

    Remedy: Mercedes will notify owners, and dealers will inspect the locking of the seatback on the affected vehicles and replace the seatback lock, as necessary, free of charge. An interim owner letter was mailed on April 12, 2019 to notify owners. Owners will receive a second notification when the remedy is available. Owners may contact Mercedes-Benz customer service at 1-800-367-6372. MBUSA's number for this recall is 2019040007.

  4. NHTSA 18V456000Jul 10, 2018Structure & Body10,826 vehicles

    Structure:body

    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.

    Remedy: 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.

  5. NHTSA 18V207000Mar 29, 2018Structure & Body3,088 vehicles

    Seats

    Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2018 C43 AMG 4Matic Coupe, C300 Coupe, C300 4Matic Coupe, C300 4Matic Cabriolet, C300 Cabriolet, C43 AMG 4Matic Cabriolet and C63S AMG Cabriolet, 2017 C63 AMG Cabriolet, C63S AMG Coupe and C63 AMG Coupe, 2018 E400 Coupe and E400 4Matic Coupe vehicles. The seatbacks of the front seats may not properly lock on the right side of the seat.

    Risk: If the seatback does not properly lock, in the event of a crash, the seatbacks may fold forward, increasing the risk of injury.

    Remedy: MBUSA will notify owners, and dealers will inspect the locking of the seatbacks, replacing the seatbacks lock, as necessary, free of charge. The recall is expected to begin May 25, 2018. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2018040007.

Structure & Body complaints by C300 model year

Raw complaint counts per model year; newer years have had less time to accumulate complaints.

  1. 201039 (9%)
  2. 201153 (11%)
  3. 201254 (20%)
  4. 201358 (22%)
  5. 201411 (12%)
  6. 201562 (16%)
  7. 201629 (10%)
  8. 201724 (11%)
  9. 201815 (15%)
  10. 20197 (10%)
  11. 20206 (18%)
  12. 20210 (0%)
  13. 20222 (8%)
  14. 20231 (5%)
  15. 20241 (9%)
  16. 20251 (25%)

Frequently asked questions

How common are structure and body problems in the 2018 Mercedes-Benz C300?
NHTSA lists 15 Structure & Body complaints for the 2018 C300, which is 15% of the 99 total complaints filed for that model year.
Is there a recall for the 2018 Mercedes-Benz C300 roof panel?
Yes. Recall 23V854000 covers a front roof panel bonding issue on 2014-2020 C-Class and related models, and recall 21V197000 covers a similar bonded panel issue on 2015-2020 C300s. Dealers replace the front panel free of charge.
At what mileage do structure and body issues typically show up?
The median mileage at failure for Structure & Body complaints on the 2018 C300 is 49,000 miles.
Have structure and body issues caused crashes on the 2018 C300?
NHTSA data shows 2 crashes linked to Structure & Body complaints for the 2018 C300, with no fires or injuries reported.
Are seatback locks part of the structure and body recalls?
Yes. Recalls 19V130000 and 18V207000 both address seatback locking issues on 2017-2018 C300 Coupe and Cabriolet models.

Sources: NHTSA Office of Defects Investigation complaint and recall databases; U.S. EPA fuel economy data; NHTSA 5-Star Safety Ratings. Complaints are unverified owner reports.

Data updated Sep 24, 2026. Read the methodology and data sources. The Complaint Index is based on NHTSA owner complaints and recalls; it is not a reliability rating.