2015 Mercedes-Benz ML400

The 2015 Mercedes-Benz ML400 is a mid-size luxury SUV that was praised for its comfortable ride, luxurious interior, and powerful engine. The ML400 specifically features a 3.0L Twin-Turbo V6 engine producing 329 horsepower and 354 lb-ft of torque. Other engine options available for the 2015 ML-Class include a 2.1L Diesel Inline-4, a 3.5L Naturally Aspirated V6, and a 5.5L Twin Turbo V8. All engines were paired with a 7G-TRONIC PLUS 7-speed automatic transmission. Owners often liked the ML400’s smooth power delivery and upscale features, but some disliked the relatively high running costs and potential for expensive repairs.

Engine

3.0L Twin-Turbo V6

• Oil Leaks
  • Description/Symptoms: Oil leaks can develop from various locations, including the valve cover gaskets, oil filter housing, and turbocharger oil lines. Symptoms include visible oil drips, burning oil smell, and low oil level.
  • Solution: Replacing the leaking gaskets or seals, and/or the oil filter housing.
  • Estimated Cost to Fix: $200 - $1,500+, depending on the location of the leak.
  • Recalls: None Found
• Turbocharger Issues
  • Description/Symptoms: The turbochargers can experience failures, leading to reduced engine power, unusual noises (whining or screeching), and potential check engine lights.
  • Solution: Replacing the faulty turbocharger(s).
  • Estimated Cost to Fix: $2,000 - $4,000+ per turbocharger (parts and labor).
  • Recalls: None Found

Transmission

7G-TRONIC PLUS 7-speed Automatic

• Torque Converter Issues
  • Description/Symptoms: Some owners have reported issues with the torque converter, leading to shuddering or vibrations during acceleration, particularly at lower speeds.
  • Solution: Replacement of the torque converter.
  • Estimated Cost to Fix: $1,500 - $3,000+
  • Recalls: None Found
• Valve Body Issues
  • Description/Symptoms: Malfunctions in the valve body can lead to harsh shifting, delayed engagement, or failure to shift at all.
  • Solution: Valve body replacement or rebuild.
  • Estimated Cost to Fix: $1,000 - $2,500+
  • Recalls: None Found

Suspension

• Air Suspension Problems (if equipped)
  • Description/Symptoms: The Airmatic suspension (if equipped) can experience leaks in the air struts or failure of the air compressor. This can lead to a sagging suspension, uneven ride height, or the inability to adjust the ride height.
  • Solution: Replacing the faulty air strut(s) and/or air compressor.
  • Estimated Cost to Fix: $800 - $2,000+ per strut; $500 - $1,500+ for the compressor.
  • Recalls: None Found

Electrical

• Battery Drain Issues
  • Description/Symptoms: Some owners have reported excessive battery drain, especially if the vehicle is not driven frequently. This can lead to difficulty starting the engine.
  • Solution: Identifying and addressing the source of the parasitic drain (e.g., faulty module, aftermarket accessories).
  • Estimated Cost to Fix: Varies widely depending on the cause; $100 - $1,000+
  • Recalls: None Found
• Electronic Control Unit (ECU) or Module Failures
  • Description/Symptoms: Various ECUs or modules (e.g., SAM – Signal Acquisition Module) can fail, leading to a wide range of problems, including malfunctioning lights, sensors, or other systems.
  • Solution: Replacing the faulty ECU or module and programming it to the vehicle.
  • Estimated Cost to Fix: $500 - $2,000+ per module
  • Recalls: None Found

Exterior

• Sunroof Issues
  • Description/Symptoms: The sunroof mechanism can sometimes malfunction, leading to difficulty opening or closing, or unusual noises.
  • Solution: Repairing or replacing the sunroof mechanism.
  • Estimated Cost to Fix: $300 - $1,000+
  • Recalls: None Found

Interior

• Malfunctioning COMAND System
  • Description/Symptoms: The COMAND infotainment system can experience software glitches, freezing, or complete failure.
  • Solution: Software updates, or replacement of the COMAND unit.
  • Estimated Cost to Fix: $200-$500+ for software updates; $1,000 - $3,000+ for unit replacement.
  • Recalls: None Found

Summary

The 2015 Mercedes-Benz ML400, while a luxurious and enjoyable vehicle, can be prone to certain issues. Engine oil leaks and potential turbocharger problems are the most significant concerns regarding the 3.0L V6 engine. Transmission issues can also be costly to repair. The air suspension system (if equipped) can also contribute to repair expenses. Battery drain and module failures can present further electrical issues. The COMAND system may have software issues. These issues can range in severity from minor inconveniences to major repairs, potentially resulting in high ownership costs.