2018 Mercedes-Benz S 450 problems and owner complaints
Explore the records behind recurring owner reports.
Key facts
7 owner complaints analyzed
8 distinct recall campaigns
44,913 mi median reported failure mileage
Scope: 2018 model year. Data snapshot: . 4 complaints include usable failure mileage.
This selection has limited data. It remains available for lookup but is excluded from search indexing.
Most common problems
Forward Collision Avoidance: Automatic Emergency Braking is the most frequently named component, appearing in 2 of 7 complaints (28.6%). A complaint can name multiple components.
| Topic | Matching reports | Share of complaints |
|---|---|---|
| Braking behavior | 3 | 42.9% |
| Transmission and shifting | 1 | 14.3% |
| Steering behavior | 1 | 14.3% |
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 |
|---|---|
| Forward Collision Avoidance: Automatic Emergency Braking | 2 |
| Service Brakes | 2 |
| Power Train | 1 |
| Seat Belts | 1 |
| Steering | 1 |
| Unknown Or Other | 1 |
Forward Collision Avoidance: Automatic Emergency Braking: 2; Service Brakes: 2; Power Train: 1; Seat Belts: 1; Steering: 1; Unknown Or Other: 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 | 1 |
| 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: 1; 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
25,000 to 49,999 miles has the most reports with usable mileage (2). 3 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 | 1 |
| 2023 | 3 |
| 2024 | 1 |
| 2025 | 1 |
2017: 1; 2019: 1; 2023: 3; 2024: 1; 2025: 1
Pattern summary
Forward Collision Avoidance: Automatic Emergency Braking 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 ↗