2018 Mercedes-Benz S450

The 2018 Mercedes-Benz S450 is a luxury sedan known for its comfortable ride, opulent interior, and advanced technology. The S450 is equipped with a 3.0L Turbocharged V6 engine producing 362 horsepower and 369 lb-ft of torque. Other engine options available in the 2018 S-Class lineup include the S560 with a 4.0L V8 Biturbo engine, and the S63 AMG with a handcrafted AMG 4.0L V8 Biturbo engine. All engines are paired with a 9G-TRONIC 9-speed automatic transmission. Owners typically praise the S450 for its smooth ride, luxurious features, and quiet cabin. Common complaints revolve around the complexity of the infotainment system and potential for expensive repairs.

Engine

3.0L Turbocharged V6

• Oil Leaks
  • Description/Symptoms: Oil leaks can occur from various locations, including the valve cover gaskets, oil filter housing, and rear main seal. Symptoms include visible oil drips under the car, the smell of burning oil, and low oil levels.
  • Solution: Replacing the leaking gasket or seal.
  • Estimated Cost to Fix: $200 - $1500+ depending on the location and complexity of the repair.
  • Recalls: None Found
• Turbocharger Issues
  • Description/Symptoms: Potential for turbocharger failure, leading to reduced engine power, unusual noises (whining, screeching), and possible check engine light.
  • Solution: Replacing the faulty turbocharger.
  • Estimated Cost to Fix: $2,000 - $4,000+
  • Recalls: None Found

Transmission

9G-TRONIC 9-Speed Automatic

• Rough Shifting/Hesitation
  • Description/Symptoms: Some owners have reported experiencing rough or delayed shifting, particularly when downshifting. This can manifest as a noticeable jerk or hesitation when accelerating or decelerating.
  • Solution: A software update to the transmission control module (TCM) or, in more severe cases, replacement of the valve body.
  • Estimated Cost to Fix: $150 - $300 for a software update; $1,500 - $3,000+ for valve body replacement.
  • Recalls: None Found

Suspension

• AIRMATIC Air Suspension Problems
  • Description/Symptoms: The AIRMATIC air suspension can experience issues with leaks in the air struts or failure of the air compressor. This results in a sagging vehicle, uneven ride height, and a bumpy ride. Warning lights on the dashboard may also illuminate.
  • Solution: Replacing the faulty air strut(s) or air compressor.
  • Estimated Cost to Fix: $1,000 - $2,500+ per strut; $800 - $1,500+ for the compressor.
  • Recalls: None Found

Electrical

• COMAND Infotainment System Issues
  • Description/Symptoms: The COMAND system can experience glitches, freezing, and connectivity problems. These can manifest as unresponsive screens, difficulty pairing Bluetooth devices, and navigation errors.
  • Solution: Software updates can sometimes resolve these issues. In more severe cases, replacement of the COMAND unit may be necessary.
  • Estimated Cost to Fix: $100 - $300 for software update; $1,500 - $3,000+ for COMAND unit replacement.
  • Recalls: None Found
• Battery Drain
  • Description/Symptoms: Some owners have reported experiencing excessive battery drain, leading to difficulty starting the vehicle, especially if it sits for extended periods.
  • Solution: Identifying and addressing the source of the parasitic draw. This may involve replacing a faulty module or repairing damaged wiring.
  • Estimated Cost to Fix: $100 - $1,000+ depending on the source of the drain.
  • Recalls: None Found

Interior

• Sunroof Issues
  • Description/Symptoms: The sunroof mechanism can sometimes fail, leading to difficulty opening or closing the sunroof. This may be accompanied by unusual noises or binding.
  • Solution: Repair or replacement of the sunroof motor or mechanism.
  • Estimated Cost to Fix: $500 - $1,500+
  • Recalls: None Found

Exterior

• Sensor Failures (Parking Sensors, Blind Spot Monitoring)
  • Description/Symptoms: The parking sensors and blind spot monitoring system can experience failures due to sensor damage or wiring issues. This can lead to false alarms or a complete loss of functionality.
  • Solution: Replacing the faulty sensor or repairing the wiring.
  • Estimated Cost to Fix: $200 - $800+ per sensor depending on location.
  • Recalls: None Found

Summary

The 2018 Mercedes-Benz S450, while offering a luxurious driving experience, has some potential issues that buyers should be aware of. The air suspension is a major area of concern due to its potential for costly repairs. Engine oil leaks and electrical system glitches also show up. While software updates can fix some problems, other problems require part replacements which can be quite expensive. Buyers should carefully inspect the vehicle, obtain a pre-purchase inspection, and be aware of the potential for higher maintenance costs associated with a luxury vehicle.