2018 Mercedes-Benz S500L

The 2018 Mercedes-Benz S500L represents the pinnacle of luxury sedans, offering a refined driving experience and a wealth of advanced technology. In the US Market, the S500L was sold as the S560L which featured a 4.0L Biturbo V8 engine rated at 463 horsepower and 516 lb-ft of torque. It was equipped with a 9G-TRONIC 9-speed automatic transmission. Owners generally praise the S500L (S560L in US) for its opulent interior, smooth ride quality, and powerful engine. Criticisms often include the complexity of the infotainment system and the high cost of maintenance and repairs.

Engine

4.0L Biturbo V8 (M176)

• Turbocharger Failure
  • Description/Symptoms: Whining or screeching noise from the engine, loss of power, check engine light. Internal components within the turbocharger can fail prematurely, leading to decreased performance.
  • Solution: Turbocharger replacement.
  • Estimated Cost to Fix: $2,500 - $4,500+
  • Recalls: None Found
• Oil Leaks
  • Description/Symptoms: Visible oil leaks on the engine, oil consumption, burning oil smell. Common leak locations include valve cover gaskets, oil cooler lines, and the rear main seal.
  • Solution: Replace leaking gaskets or seals.
  • Estimated Cost to Fix: $200 - $1,500+ depending on the location and severity of the leak.
  • Recalls: None Found

Transmission

9G-TRONIC 9-Speed Automatic (725.0)

• Rough Shifting/Hesitation
  • Description/Symptoms: Harsh or jerky shifts between gears, hesitation when accelerating, especially during downshifts. Can be intermittent or persistent.
  • Solution: Software update of the transmission control module (TCM). If the issue persists, valve body replacement or full transmission replacement may be required.
  • Estimated Cost to Fix: $200 (software update) to $4,000+ (transmission replacement)
  • Recalls: None Found
• Torque Converter Issues
  • Description/Symptoms: Shuddering or vibrations at low speeds, particularly during light acceleration. Can be more pronounced when the transmission is cold.
  • Solution: Torque converter replacement.
  • Estimated Cost to Fix: $1,500 - $3,000+
  • Recalls: None Found

Suspension

• AIRMATIC Suspension Failure
  • Description/Symptoms: Vehicle sagging on one or more corners, suspension warning lights, inability to adjust ride height, air compressor running constantly. Failure of the air struts is a common issue.
  • Solution: Replace faulty air strut(s), check for leaks in the air lines, replace air compressor if necessary.
  • Estimated Cost to Fix: $1,200 - $2,500+ per strut; $500 - $1,000 for the compressor.
  • Recalls: None Found
• Airmatic Compressor Failure
  • Description/Symptoms: Suspension warning light, car sagging, and inability to adjust the height of the vehicle.
  • Solution: Replace the airmatic compressor
  • Estimated Cost to Fix: $500 - $1,000
  • Recalls: None Found

Electrical

• Infotainment System Malfunctions (COMAND System)
  • Description/Symptoms: System freezing, screen going blank, unresponsive buttons, navigation errors, Bluetooth connectivity issues.
  • Solution: Software update, replacement of the COMAND unit if the issue persists.
  • Estimated Cost to Fix: $150 - $300 (software update), $1,500 - $3,000+ (COMAND unit replacement).
  • Recalls: None Found
• Battery Drain
  • Description/Symptoms: Car failing to start, needing frequent jump starts, electrical systems malfunctioning. Can be caused by a parasitic drain from a faulty module or component.
  • Solution: Diagnose and repair the source of the parasitic drain. Replacing the battery is also common.
  • Estimated Cost to Fix: $150 - $300 (diagnostic), $200 - $500+ (battery replacement), $100 - $1,000+ (depending on the component causing the drain).
  • Recalls: None Found

Exterior

• Panoramic Roof Issues
  • Description/Symptoms: Squeaking or creaking noises when opening or closing, difficulty opening or closing, water leaks.
  • Solution: Lubricate the tracks and seals, repair or replace damaged components of the panoramic roof mechanism, reseal the roof to address leaks.
  • Estimated Cost to Fix: $100 - $500 (lubrication and minor repairs), $1,000 - $3,000+ (major repairs or replacement).
  • Recalls: None Found
• Sensor Malfunctions (Parking Sensors, Blind Spot Monitoring)
  • Description/Symptoms: False alarms, failure to detect objects, error messages. Can be caused by dirt, damage, or faulty sensors.
  • Solution: Clean or replace faulty sensors.
  • Estimated Cost to Fix: $100 - $300 per sensor.
  • Recalls: None Found

Interior

• Seat Motor Failure
  • Description/Symptoms: Seat not adjusting, clicking noises when attempting to adjust, limited range of motion.
  • Solution: Replace faulty seat motor or repair the seat adjustment mechanism.
  • Estimated Cost to Fix: $300 - $800+
  • Recalls: None Found
• Sunroof rattles
  • Description/Symptoms: Rattling when going over uneven roads and speedbumps.
  • Solution: Remove and clean old grease, lubricate with Krytox GPL 205 grease.
  • Estimated Cost to Fix: $150-$400
  • Recalls: None Found

Summary

The 2018 Mercedes-Benz S500L (S560L) offers exceptional luxury, but it’s important to be aware of potential issues. Engine and transmission issues, while not extremely widespread, can be costly to repair. Suspension problems, particularly with the AIRMATIC system, are relatively common and can lead to significant expenses. Electrical issues, especially with the infotainment system, are also a concern. While some issues are minor, others can be quite severe and expensive to address, making a thorough pre-purchase inspection essential.