2016 Mercedes-Benz GL550

The 2016 Mercedes-Benz GL550 is a luxury SUV known for its powerful engine, spacious interior, and comfortable ride. It features a 4.7L twin-turbo V8 engine producing 429 horsepower and 516 lb-ft of torque. Other engine options include the GL350 BlueTEC with a 3.0L diesel V6, the GL450 with a 3.0L twin-turbo V6, and the AMG GL63 with a 5.5L twin-turbo V8. All models are equipped with a 7G-TRONIC PLUS 7-speed automatic transmission. Owners generally appreciate the GL550’s performance, luxurious features, and ample space, but some common complaints revolve around the high cost of maintenance and repairs, as well as certain electrical and suspension issues.

Engine

4.7L Twin-Turbo V8 (M278)

• Oil Leaks from Valve Cover Gaskets
  • Description/Symptoms: Oil leaks are common as the valve cover gaskets age. Signs include oil puddles under the vehicle, burning oil smell, and visible oil around the valve covers.
  • Solution: Replace the valve cover gaskets.
  • Estimated Cost to Fix: $600 - $1000+
  • Recalls: None Found
• Turbocharger Oil Supply Line Leaks
  • Description/Symptoms: Oil leaks from the turbocharger oil supply lines can occur, leading to oil consumption and potential turbocharger damage.
  • Solution: Replace the turbocharger oil supply lines and associated seals.
  • Estimated Cost to Fix: $800 - $1500+
  • Recalls: None Found

3.0L Diesel V6 (OM642)

• Oil Cooler Seal Leaks
  • Description/Symptoms: Leaks from the oil cooler seals can lead to significant oil loss.
  • Solution: Replace the oil cooler seals. This job is labor-intensive as it requires removing the intake manifold.
  • Estimated Cost to Fix: $1200 - $2000+
  • Recalls: None Found
• Diesel Particulate Filter (DPF) Issues
  • Description/Symptoms: DPF can become clogged, leading to reduced engine performance, increased fuel consumption, and warning lights.
  • Solution: DPF regeneration, cleaning, or replacement.
  • Estimated Cost to Fix: $500 - $3000+ (depending on the repair needed)
  • Recalls: None Found

Transmission

7G-TRONIC PLUS 7-Speed Automatic (722.9)

• Valve Body Issues
  • Description/Symptoms: Erratic shifting, harsh shifts, delayed engagement, or slipping.
  • Solution: Valve body replacement or rebuild.
  • Estimated Cost to Fix: $1500 - $3000+
  • Recalls: None Found
• Torque Converter Failure
  • Description/Symptoms: Shuddering at low speeds, especially during acceleration, or complete transmission failure.
  • Solution: Replace the torque converter.
  • Estimated Cost to Fix: $2000 - $4000+
  • Recalls: None Found

Suspension

• Air Suspension Compressor Failure
  • Description/Symptoms: The air suspension system fails to maintain the proper ride height. The vehicle may sag on one or more corners. The compressor may be loud or not run at all.
  • Solution: Replace the air suspension compressor.
  • Estimated Cost to Fix: $800 - $1800+
  • Recalls: None Found
• Air Strut Leaks
  • Description/Symptoms: Air leaks from the air struts cause the vehicle to sag, especially overnight.
  • Solution: Replace the leaking air strut(s).
  • Estimated Cost to Fix: $1000 - $2500+ per strut
  • Recalls: None Found

Electrical

• Faulty Steering Angle Sensor
  • Description/Symptoms: ABS, ESP, and other warning lights illuminated on the dashboard. Power steering assist might be reduced.
  • Solution: Replace the steering angle sensor.
  • Estimated Cost to Fix: $500 - $1000+
  • Recalls: None Found
• Battery Drain Issues
  • Description/Symptoms: The battery drains quickly, especially when the vehicle is parked. This can be caused by a parasitic drain from a faulty module or accessory.
  • Solution: Diagnose and repair the source of the parasitic drain. This may involve replacing a faulty module or accessory.
  • Estimated Cost to Fix: $200 - $1000+ (depending on the source of the drain)
  • Recalls: None Found

Exterior

• No Issues Found

Interior

• Malfunctioning COMAND System
  • Description/Symptoms: The COMAND infotainment system may freeze, crash, or exhibit intermittent functionality.
  • Solution: Software update or replacement of the COMAND unit.
  • Estimated Cost to Fix: $500 - $2000+
  • Recalls: None Found

Summary

The 2016 Mercedes-Benz GL550, while offering a luxurious driving experience, can be prone to several issues, particularly within its engine, transmission, suspension, and electrical systems. The air suspension components, specifically the compressor and struts, are known failure points. Engine oil leaks are common, especially with the 4.7L V8 and 3.0L diesel V6. Transmission valve body failures can lead to costly repairs. Electrical issues, such as battery drain and steering angle sensor malfunctions, also surface regularly. The severity of these issues ranges from minor inconveniences to major repairs costing thousands of dollars. Prospective buyers should be aware of these potential problems and factor them into their ownership costs.