2018 Mercedes-Benz GLS550
The 2018 Mercedes-Benz GLS550 is a luxurious and capable SUV known for its spacious interior, powerful engine, and comfortable ride. The GLS550 is equipped with a 4.7-liter biturbo V8 engine, which delivers 449 horsepower and 516 lb-ft of torque. Other engine options available for the 2018 GLS-Class include a 3.0-liter V6 in the GLS450 and a hand-built 5.5-liter AMG V8 in the GLS63 AMG. All GLS models are equipped with a 9G-TRONIC 9-speed automatic transmission. Many owners appreciate the GLS550’s refined interior and smooth driving experience. However, some common complaints include electronic glitches, expensive maintenance, and occasional suspension issues.
Engine
4.7L Biturbo V8
- Oil Leaks
- Description/Symptoms: Oil leaks are reported from various locations, including valve cover gaskets, oil filter housing, and turbocharger lines. Symptoms include visible oil leaks, burning oil smell, and low oil level warning light.
- Solution: Replacing the leaking gaskets, seals, or lines is the common solution.
- Estimated Cost to Fix: $200 - $1500+ depending on the location and complexity of the repair.
- Recalls: None Found
- Turbocharger Issues
- Description/Symptoms: Some owners have reported turbocharger failures or malfunctions. Symptoms may include reduced power, whistling noises, and potentially an engine check light.
- Solution: Diagnosis to determine cause of failure of the Turbocharger. Replacement of the turbocharger may be necessary.
- Estimated Cost to Fix: $2,000 - $4,000+
- Recalls: None Found
Transmission
9G-TRONIC 9-Speed Automatic
- Rough Shifting
- Description/Symptoms: Some owners have reported experiencing rough or delayed shifting, particularly between certain gears.
- Solution: In some cases, a software update can resolve the issue. If the problem persists, valve body replacement or transmission rebuild/replacement may be necessary.
- Estimated Cost to Fix: $200 - $6,000+
- Recalls: None Found
Suspension
- Air Suspension Problems
- Description/Symptoms: The Airmatic suspension system can experience issues such as air leaks, compressor failure, or malfunctioning sensors. Symptoms include the vehicle sitting low on one side, the suspension not adjusting properly, or a warning light illuminating on the dashboard.
- Solution: Replacing the faulty air springs, compressor, or sensors.
- Estimated Cost to Fix: $500 - $3,000+ depending on the affected component and location.
- Recalls: None Found
Electrical
- Infotainment System Glitches
- Description/Symptoms: The COMAND infotainment system can experience glitches, such as freezing, lagging, or unresponsive controls.
- Solution: Software updates may resolve some issues. In more severe cases, replacement of the head unit may be necessary.
- Estimated Cost to Fix: $100 - $2,000+
- Recalls: None Found
- Battery Drain
- Description/Symptoms: Some owners have reported issues with excessive battery drain, leading to a dead battery, especially if the vehicle sits for extended periods.
- Solution: Diagnosing and addressing the parasitic draw, which may involve identifying faulty modules or components.
- Estimated Cost to Fix: $150 - $500+
- Recalls: None Found
Exterior
No Issues Found
Interior
- Sunroof Issues
- Description/Symptoms: Some owners have reported issues with the sunroof malfunctioning, such as getting stuck, making excessive noise, or leaking.
- Solution: Repairing or replacing the sunroof motor, track, or seals.
- Estimated Cost to Fix: $300 - $1,500+
- Recalls: None Found
Summary
The 2018 Mercedes-Benz GLS550, while a luxurious and powerful SUV, does have some common issues owners have reported. The most frequently mentioned problems involve the air suspension, electrical glitches, and oil leaks. While some issues, such as infotainment glitches, may be minor, others, like air suspension or turbocharger failures, can be quite costly to repair. Potential buyers should be aware of these potential issues and have a pre-purchase inspection performed by a qualified mechanic.