Mercedes-Benz S 450 problems and owner complaints
Explore the records behind recurring owner reports.
Key facts
14 owner complaints analyzed
14 distinct recall campaigns
21,850 mi median reported failure mileage
Scope: 2018 to 2020 model years. Data snapshot: . 6 complaints include usable failure mileage.
This selection has limited data. It remains available for lookup but is excluded from search indexing.
Most common problems
Unknown Or Other is the most frequently named component, appearing in 4 of 14 complaints (28.6%). A complaint can name multiple components.
| Topic | Matching reports | Share of complaints |
|---|---|---|
| Braking behavior | 3 | 21.4% |
| Transmission and shifting | 1 | 7.1% |
| Steering behavior | 1 | 7.1% |
| Fuel system concerns | 1 | 7.1% |
Topic matches use published keyword rules. They describe mentions, including negations or comparisons, and do not confirm a diagnosis. Read the matching rules.
Component breakdown
Number of unique complaints naming each component. Top eight shown.
| Category | Count |
|---|---|
| Unknown Or Other | 4 |
| Service Brakes | 3 |
| Forward Collision Avoidance: Automatic Emergency Braking | 2 |
| Power Train | 2 |
| Fuel/Propulsion System | 1 |
| Seat Belts | 1 |
| Steering | 1 |
| Vehicle Speed Control | 1 |
Unknown Or Other: 4; Service Brakes: 3; Forward Collision Avoidance: Automatic Emergency Braking: 2; Power Train: 2; Fuel/Propulsion System: 1; Seat Belts: 1; Steering: 1; Vehicle Speed Control: 1
Reported problems by failure mileage
Complaint counts in mileage bands. These are not failure rates per vehicle or mile.
| Category | Count |
|---|---|
| Under 25,000 | 3 |
| 25,000 to 49,999 | 2 |
| 50,000 to 74,999 | 0 |
| 75,000 to 99,999 | 1 |
| 100,000 to 149,999 | 0 |
| 150,000 and above | 0 |
Under 25,000: 3; 25,000 to 49,999: 2; 50,000 to 74,999: 0; 75,000 to 99,999: 1; 100,000 to 149,999: 0; 150,000 and above: 0
Under 25,000 miles has the most reports with usable mileage (3). 8 complaints have missing, zero or invalid mileage.
Complaints over time
Year the complaint was filed, not the vehicle model year or incident year. The snapshot year is partial.
| Category | Count |
|---|---|
| 2017 | 1 |
| 2019 | 2 |
| 2020 | 1 |
| 2023 | 3 |
| 2024 | 2 |
| 2025 | 3 |
| 2026 | 2 |
2017: 1; 2019: 2; 2020: 1; 2023: 3; 2024: 2; 2025: 3; 2026: 2
Pattern summary
Unknown Or Other leads the component reports. Braking behavior appears in 3 complaint narratives. Transmission and shifting appears in 1 complaint narratives. Steering behavior appears in 1 complaint narratives. Use these patterns to inspect individual reports and prepare questions for a mechanic.
Calculated from recorded counts. An AI narrative has not been published for this selection.
Complaint evidence
Examples provide context, not a representative sample or a verified diagnosis.
Owner report 11217774 · 2019-06-04 (June 4, 2019)
TL* THE CONTACT OWNS A 2018 MERCEDES-BENZ S450. WHILE DRIVING 75 MPH WITH THE CRUISE CONTROL ENGAGED, THE AUTOMATIC BRAKING ACTIVATED ON ITS OWN IN TRAFFIC. THE CONTACT HAD TO DEPRESS THE BRAKE PEDAL TO DISENGAGE THE CRUISE CONTROL IN ORDER TO DRIVE SAFELY. THE VEHICLE WAS TAKEN TO MERCEDES-BENZ OF ALEXANDRIA (200 S PICKETT ST, ALEXANDRIA, VA 22304, [phone removed]) TO BE DIAGNOSED, BUT THE FAILURE COULD NOT BE DUPLICATED. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS 49,826.
Owner-reported narrative. 49,826 miles reported. Look up ODI 11217774 at NHTSA ↗
Owner report 11509192 · 2023-02-26 (February 26, 2023)
I’m reporting this safety concern and seeking advisement from those more knowledgeable than myself on this issue. Recently, as I attempted to actuate the brake of my vehicle. My right foot was entangled with the brake pedal as I moved it from the acceleration pedal to the brake pedal in observance of a “Stop Sign.” I barely avoided what surely would have been a catastrophic collision with another vehicle. The incident occurred in a split second. The shoe of my right foot was entangled with the lower right corner of the underside of the brake…
Owner-reported narrative. Look up ODI 11509192 at NHTSA ↗
Owner report 11637720 · 2025-01-22 (January 22, 2025)
The contact owns a 2018 Mercedes-Benz S450. The contact stated while driving at an undisclosed speed, the gear shifter independently shifted into neutral. The contact had to hold down the gear shifter for about 30 seconds before the system was reset. Additionally, the check engine warning light was later illuminated. The vehicle was taken to the dealer where it was diagnosed with transmission valve body failure. The contact was informed that the transmission valve body needed to be replaced. The vehicle was not repaired. The manufacturer was ma…
Owner-reported narrative. 89,000 miles reported. Look up ODI 11637720 at NHTSA ↗
Owner report 11524278 · 2023-05-29 (May 29, 2023)
Steering wheel became extremely stiff to turn and a message that read “steering malfunction increase physical effort” appeared while driving at around 30 mph while in a vacation trip, not only was this extremely unsettling since it happened suddenly but I had to act fast to avoid a collision with other vehicles, once I made it to a safe location I shut the vehicle off and restarted after 15 minutes and it seem drivable again but left me extremely concerned as I am 500 miles away from with no dealerships open to have it looked since is Memorial …
Owner-reported narrative. Look up ODI 11524278 at NHTSA ↗
Owner report 11694134 · 2025-10-17 (October 17, 2025)
The fuel pump My car stopped on the highway [XXX] on [XXX] with my children in the car with no warning at all. I was so lucky nobody hit us and it took 20 minutes of trying to start it to get off of the highway to a gas station where it cut off again The dealer said it is a known problem however my vin number was included despite the fact that they know that the 2020 mercedes benz s450 has an issue that should be recalled due to the severity of the situation and safety of the public. Warning lights did not come on until the car totally stopped…
Owner-reported narrative. Look up ODI 11694134 at NHTSA ↗
Recalls by model year
All campaigns in the snapshot affecting each model year, including recalls announced years later.
Recall campaigns
Shared campaigns appear once in each affected model year.
| Category | Count |
|---|---|
| 2018 | 8 |
| 2019 | 8 |
| 2020 | 4 |
2018: 8; 2019: 8; 2020: 4