2018 Mercedes-Benz S-Class Common Problems & Defect Telemetry
Authoritative defect intelligence synthesized from 29 verified NHTSA owner complaints, 0 federal safety recalls, and interquartile failure mileage telemetry.
The 2018 Mercedes-Benz S-Class receives a 7.6/10 MazicBay Reliability Index based on 29 verified NHTSA federal complaints and 0 safety recalls. The primary reported failure mode is Electric Power Steering Assist & Suspension Noise Reports with a median failure point at 55,000 miles (IQR: 35,000 – 75,000 mi). Out-of-warranty repairs benchmark at $450 – $1,400 .
6.4 complaints / 10k sold
Verified US federal records
Crash, fire & stall audit
0 Active / Free Remedies
Top Reported Problem Clusters (6)
Electric Power Steering Assist & Suspension Noise Reports
- Sudden loss of electric power steering assist
- Steering wheel pull or highway wander
- Clunking / knocking noise over bumps
“Vehicle had a low tire, vehicle indicated it needed to be driven for recalibration of the sensor(s). Took vehicle for short drive up two lane road. Turned around and headed back to where was staying and upon acceleration the vehicle seemed to have pulled off the road but come ...”
“The engine failed while my friend was driving. The car is available for inspection. My friend almost got into a car accident because the car started shaking and the steering wheel closed up before the engine completely failed. Additionally, the airbags did not go off. It could...”
“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 av...”
Engine Stalling, Oil Consumption & Cooling Defect Reports
- Engine sudden stall / hesitation while driving
- Abnormal oil burning / consumption
- Check Engine Light (MIL) flashing
- Engine overheating / coolant loss
“Excessive engine oil lead from the back seal. Also, slow coolant leak. The car has a low mileage of 46k.”
“My 2018 S560 Mercedes occasionally misfires upon acceleration. This has happened at six times over the past three years. When this happens, the engine loses power, starts to shake, and the check engine light comes on. This happened when I was trying to pass a car on US 301 a w...”
“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 en...”
Service Brakes, ABS Actuator & Master Cylinder Reports
- Spongy or hard brake pedal travel
- ABS / Brake warning light illuminated
- Extended stopping distance / pedal vibration
“Vehicle had a low tire, vehicle indicated it needed to be driven for recalibration of the sensor(s). Took vehicle for short drive up two lane road. Turned around and headed back to where was staying and upon acceleration the vehicle seemed to have pulled off the road but come ...”
“Driving on interstate 95 in South Carolina in the high speed lane Saturday December 2 2023 late morning. Adaptive cruise control, lane keep assist, self driving modes engaged. No traffic in front, large semi truck next to passenger side about equal to side mirror, I believe it...”
“The contact owns a 2018 Mercedes-Benz S450. The contact stated while driving at an undisclosed speed, the contact attempted to depress the brake; however, the vehicle failed to decelerate and slow as needed. The contact stated that the brakes failed to work as needed. The cont...”
Airbag Occupant Detection & Inflator Defect Reports
- SRS Airbag warning lamp illuminated
- Passenger occupant classification sensor failure
- Seat belt retractor lockup
“The Squib For PRE-SAFE(R) Pulse '' Front Passenger'' Has A S560 w222 model airbag sensors problem an defective parts needs be investigated”
“1. The leather cover for the dashboard has peeled up on the passenger side. The vehicle is parked inside a covered garage while it is not being driven since it was purchased in 2021. 2. I am worried about the safety airbag restraints in the dashboard might not be working. 3. T...”
“The engine failed while my friend was driving. The car is available for inspection. My friend almost got into a car accident because the car started shaking and the steering wheel closed up before the engine completely failed. Additionally, the airbags did not go off. It could...”
Transmission Hesitation, Hard Shifting & Slipping Reports
- Hard gear shifts / delayed engagement into Drive/Reverse
- Transmission shudder / jerking under acceleration
- Transmission slipping between gears
“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 en...”
“Vehicle Check Engine Light turned on a Vehicle Lost power. Vehicle often hesitates upon acceleration. Convertible Top does not close as well intermittently.”
Electrical Parasitic Drain, Infotainment & Harness Reports
- Unexplained battery drain after sitting overnight
- Infotainment display / instrument cluster blackouts
- Accessory malfunction / alternator fault warnings
“The contact owns a 2018 Mercedes-Benz S560. The contact received notification of NHTSA Campaign Number: 21V058000 (Communication, Electrical System) however, the part to do the recall repair was unavailable. The contact took the vehicle to the local dealer and it was confirmed...”
Pre-Purchase Inspection Checklist for 2018 Mercedes-Benz S-Class
Before purchasing a used 2018 Mercedes-Benz S-Class, perform the following targeted inspections based on reported federal defect patterns:
Scan the OBD-II port under the dash for pending freeze-frame codes (e.g. P0300 misfires, P0087 fuel rail pressure, P0420 catalytic efficiency).
Test vehicle at low-speed stop-and-go and highway merges. Check for delayed reverse engagement or gear shift shudder between 2nd and 3rd gears.
Verify that all 0 NHTSA safety recall campaigns have been performed by an authorized dealership using the VIN.
Ensure the instrument cluster, center screen, and auxiliary charging ports operate with stable 12.0V–14.4V alternator voltage.
Defect & Reliability Q&A: 2018 Mercedes-Benz S-Class
Is the 2018 Mercedes-Benz S-Class a reliable used car?
The 2018 Mercedes-Benz S-Class earns a 7.6/10 MazicBay Reliability Index based on 29 federal owner reports. Vehicles maintained under factory service schedules exhibit strong longevity past 150,000 miles.
What is the most frequent defect reported on the 2018 Mercedes-Benz S-Class?
The leading complaint category is Electric Power Steering Assist & Suspension Noise Reports, with a median failure point around 55,000 miles (IQR: 35,000 – 75,000 mi).
Are there free recall repairs available for the 2018 Mercedes-Benz S-Class?
Yes, the NHTSA records 0 safety recall campaign(s) for this model year. All safety recalls are performed 100% free of charge by authorized franchise dealerships regardless of vehicle warranty status.