2018 Mercedes-Benz SL65 AMG

The 2018 Mercedes-Benz SL65 AMG is a high-performance roadster boasting a hand-built 6.0L biturbo V12 engine producing 621 horsepower and 738 lb-ft of torque. Other engine options for the 2018 SL include a 3.0L biturbo V6 in the SL450, a 4.7L biturbo V8 in the SL550, and a 5.5L biturbo V8 in the SL63 AMG. All models use a Mercedes-Benz-produced automatic transmission. Owners often praise the SL65 AMG for its immense power, luxurious interior, and comfortable ride. Common complaints include high maintenance costs, complex electronics, and a dated infotainment system.

Engine

6.0L Biturbo V12

• Coil Pack Failure
  • Description/Symptoms: Misfires, rough idling, check engine light. Often affects individual cylinders, requiring replacement of the faulty coil pack(s).
  • Solution: Replace faulty coil pack(s).
  • Estimated Cost to Fix: $200 - $500+ per coil pack, including labor.
  • Recalls: None Found
• Turbocharger Oil Leaks
  • Description/Symptoms: Oil consumption, blue smoke from the exhaust, reduced turbocharger performance. Oil leaks often originate from turbocharger oil lines or seals.
  • Solution: Replace leaking oil lines and seals, or rebuild/replace the turbocharger(s) if necessary.
  • Estimated Cost to Fix: $500 - $3,000+, depending on the extent of the repair.
  • Recalls: None Found
• Coolant Leaks
  • Description/Symptoms: Low coolant level, overheating, visible coolant leaks under the vehicle. The V12 engine has complex cooling systems with many hoses and connections that can leak over time.
  • Solution: Locate and repair the source of the leak. This may involve replacing hoses, clamps, or other cooling system components.
  • Estimated Cost to Fix: $200 - $1,500+, depending on the location and complexity of the leak.
  • Recalls: None Found

Transmission

7G-TRONIC Automatic Transmission (All Models)

• Valve Body Issues
  • Description/Symptoms: Harsh shifting, delayed engagement, slipping between gears.
  • Solution: Replacement of the valve body.
  • Estimated Cost to Fix: $1,500 - $3,000+
  • Recalls: None Found
• Torque Converter Failure
  • Description/Symptoms: Shuddering at low speeds, transmission slipping, abnormal noises.
  • Solution: Replace the torque converter.
  • Estimated Cost to Fix: $1,000 - $3,000+
  • Recalls: None Found

Suspension

• ABC (Active Body Control) System Leaks and Failure
  • Description/Symptoms: Vehicle sagging, uneven ride height, warning messages on the instrument cluster. ABC system uses hydraulic fluid and struts to control body roll and provide a smooth ride. Components such as the pump, valve blocks, and struts can leak or fail.
  • Solution: Diagnose the specific component that is failing and replace it. This may involve replacing struts, the pump, valve blocks, or accumulators.
  • Estimated Cost to Fix: $500 - $3,000+ per component, depending on the part and labor.
  • Recalls: None Found

Electrical

• COMAND System Issues
  • Description/Symptoms: Infotainment system freezing, slow response times, navigation problems, Bluetooth connectivity issues.
  • Solution: Software updates, replacement of the COMAND unit.
  • Estimated Cost to Fix: $200 - $2,000+, depending on the issue and solution.
  • Recalls: None Found
• Battery Drain
  • Description/Symptoms: Dead battery, difficulty starting the vehicle. Can be caused by a variety of factors, including a faulty battery, parasitic draw from electrical components, or a malfunctioning alternator.
  • Solution: Diagnose the source of the battery drain and repair accordingly. This may involve replacing the battery, repairing faulty wiring, or replacing the alternator.
  • Estimated Cost to Fix: $100 - $500+, depending on the cause of the drain.
  • Recalls: None Found
• Convertible Top Malfunctions
  • Description/Symptoms: The convertible top fails to open or close properly. The top uses multiple electric motors, hydraulic pumps, and sensors.
  • Solution: Diagnose the cause of the malfunction. The motor and hydraulic components may need to be replaced
  • Estimated Cost to Fix: $300-$3,000
  • Recalls: None Found

Exterior

• Retractable Hard Top Issues
  • Description/Symptoms: Difficulty opening or closing the roof, unusual noises during operation, leaks around the seals.
  • Solution: Diagnosing and repairing the hydraulic system, sensors, or mechanical linkages involved in the roof operation.
  • Estimated Cost to Fix: $500 - $3,000+
  • Recalls: None Found

Interior

• Seat Motor Issues
  • Description/Symptoms: The seats failing to adjust in one or more directions due to a broken or stripped motor.
  • Solution: Replace the faulty motor.
  • Estimated Cost to Fix: $300-$1,000
  • Recalls: None Found

Summary

The 2018 Mercedes-Benz SL65 AMG, while offering exceptional performance and luxury, can present owners with potentially costly issues. The V12 engine, complex ABC suspension, and sophisticated electronics are prone to problems that can lead to significant repair bills. Many issues relate to the complexity of the high-performance engine, transmission, and the Active Body Control system. The potential for high maintenance costs should be a major consideration for prospective buyers.