2020 Mercedes-Benz SL550

The 2020 Mercedes-Benz SL550 is a luxury roadster known for its elegant design, powerful performance, and comfortable ride. The SL550 is powered by a 4.7-liter twin-turbo V8 engine producing 449 horsepower and 516 lb-ft of torque. It is paired with a 9G-TRONIC 9-speed automatic transmission. While lauded for its refined driving experience and luxurious features, some owners have reported specific issues. Some common complaints include electrical glitches and occasional problems with the complex roof mechanism. Others appreciate the powerful engine, comfortable interior, and smooth ride.

Engine

4.7L Twin-Turbo V8

• Oil Leaks
  • Description/Symptoms: Oil leaks from the valve cover gaskets and/or oil filter housing. Symptoms include visible oil drips under the car, burning oil smell, and low oil level warnings.
  • Solution: Replacing the valve cover gaskets and/or oil filter housing gasket.
  • Estimated Cost to Fix: $200 - $1000+ depending on the location of the leak and extent of damage.
  • Recalls: None Found
• Turbocharger Issues
  • Description/Symptoms: Whining noises from the engine, reduced power, check engine light. Can be caused by failing turbocharger seals.
  • Solution: Replacing the affected turbocharger(s).
  • Estimated Cost to Fix: $3000+
  • Recalls: None Found

Transmission

9G-TRONIC 9-Speed Automatic

• Rough Shifting
  • Description/Symptoms: Harsh or jerky shifts, especially when cold. May also include hesitation or delays when shifting.
  • Solution: A software update to the Transmission Control Module (TCM) may resolve the issue. In some cases, a transmission fluid flush and filter replacement are necessary. In other cases, valve body or conductor plate replacement may be required.
  • Estimated Cost to Fix: $300 - $3000+
  • Recalls: None Found
• Transmission Slipping
  • Description/Symptoms: The engine revs high, but the car does not accelerate properly.
  • Solution: This could indicate a more serious issue with the transmission, potentially requiring a rebuild or replacement.
  • Estimated Cost to Fix: $4000 - $8000+
  • Recalls: None Found

Suspension

• AIRMATIC Suspension Failure
  • Description/Symptoms: The vehicle may sit low on one or more corners, the ride may become harsh, or warning lights may appear on the dashboard. This can be due to leaks in the air struts, a failing compressor, or a faulty valve block.
  • Solution: Replacing the air strut(s), air suspension compressor, or valve block.
  • Estimated Cost to Fix: $1000 - $3000+ per strut, $1000+ for compressor and $500+ for valve block.
  • Recalls: None Found

Electrical

• Battery Drain Issues
  • Description/Symptoms: The battery drains quickly, especially when the car is not in use. This can lead to difficulty starting the car or complete battery failure. Possible causes include faulty modules, parasitic drains, or a failing alternator.
  • Solution: Identifying and repairing the source of the parasitic drain. This may involve testing individual modules and circuits. Replacing a faulty alternator is also common.
  • Estimated Cost to Fix: $200 - $1000+
  • Recalls: None Found
• Infotainment System Malfunctions
  • Description/Symptoms: The infotainment screen may freeze, reboot unexpectedly, or fail to respond to inputs. The navigation system, radio, or other features may also malfunction.
  • Solution: Software updates can sometimes resolve these issues. In more severe cases, the infotainment system module may need to be replaced.
  • Estimated Cost to Fix: $100 - $200 for a software update, $1000+ for module replacement.
  • Recalls: None Found
• Convertible Top Issues
  • Description/Symptoms: The convertible top may fail to open or close properly, get stuck, or make unusual noises. This can be due to issues with the hydraulic system, sensors, or latching mechanisms.
  • Solution: Diagnosing the specific cause of the problem and repairing or replacing the affected components. This may involve bleeding the hydraulic system, replacing sensors, or adjusting the latches.
  • Estimated Cost to Fix: $500 - $3000+ depending on the complexity of the repair.
  • Recalls: None Found

Exterior

• Convertible Top Leaks
  • Description/Symptoms: Water leaks into the cabin, especially during heavy rain or car washes. This can be due to worn seals or misaligned components.
  • Solution: Replacing the seals and/or realigning the convertible top components.
  • Estimated Cost to Fix: $200 - $1000+
  • Recalls: None Found

Interior

• Seat Motor Issues
  • Description/Symptoms: The seat fails to adjust properly, or makes unusual noises when adjusting. This is usually due to failing motor or faulty wiring.
  • Solution: Replace the seat motor and/or wiring harness.
  • Estimated Cost to Fix: $300 - $1000+
  • Recalls: None Found

Summary

The 2020 Mercedes-Benz SL550 offers a luxurious driving experience, but some owners have reported issues, particularly with the electrical system, convertible top, and suspension. Engine and transmission issues appear less frequently but can be costly to repair. The severity and cost of these issues vary, but potential buyers should be aware of the possibility of needing to address these problems, potentially impacting the long-term cost of ownership.