Mercedes GL-Class 2017 Common Issues: Unbelievable Reliability

The 2017 Mercedes-Benz GL-Class is known for its remarkable durability and luxury. While most owners experience stellar performance, a few common issues can arise, typically related to its sophisticated electronics and powertrain. Addressing these proactively ensures the GL-Class continues its legacy of impressive reliability.

When it comes to luxury SUVs, the Mercedes-Benz GL-Class has always stood out. For 2017, this capable vehicle, now known as the GLS, offered a blend of robust performance, opulent comfort, and advanced technology. Many owners rave about its exceptional reliability, a testament to Mercedes-Benz’s engineering prowess. However, like any complex machine, a few common points might warrant attention. Understanding these potential quirks allows any GL-Class owner to maintain their vehicle with confidence, ensuring it continues to perform at its peak for years to come. This guide will walk you through these specific areas, making ownership a smooth and enjoyable experience.

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Your Guide to the 2017 Mercedes GL-Class: Understanding Its Reliability

The 2017 Mercedes-Benz GL-Class (which transitioned to the GLS model designation during this generation) is a full-size luxury SUV that prioritizes comfort, technology, and capability. Renowned for its robust build and Mercedes-Benz’s commitment to quality, it generally offers a high level of reliability. However, as with any sophisticated vehicle, certain components can occasionally present issues. Being aware of these common points allows owners to maintain their GL-Class proactively, ensuring its legendary dependability continues.

This article delves into the most frequently reported common issues for the 2017 GL-Class. We aim to provide clear, actionable insights for owners and prospective buyers, demystifying any concerns and reinforcing the vehicle’s overall strong reputation.

Common Issues and Troubleshooting for the 2017 Mercedes GL-Class

While the 2017 GL-Class is built with exceptional quality, a few areas have been noted by owners and mechanics as potential points of concern. These are not widespread failures but rather specific components that, over time or under certain conditions, might require attention.

1. Suspension System Concerns

The GL-Class features an advanced AIRMATIC suspension system designed to provide a smooth ride and adjustable handling. While generally reliable, some owners have reported issues with air suspension leaks or compressor failures.

Symptoms:
The vehicle may sag or appear lower on one side or all around, especially after sitting for a period.
A persistent hissing sound from the suspension area when the vehicle is off.
Warning lights on the dashboard related to the suspension system.
A harsher than usual ride quality.

Causes:
Age-related degradation of rubber air springs and seals.
Condensation and debris affecting the air compressor’s lifespan.
Minor punctures or wear on air lines.

Troubleshooting & Solutions:
Leak Detection: A mechanic can use a leak detection fluid or soapy water to pinpoint leaks in air springs or lines.
Component Replacement: If leaks are found, the affected air spring, suspension strut, or air line will need to be replaced.
Compressor Service: Ensure the air dryer element in the compressor system is serviced periodically, as recommended in the maintenance schedule.
Professional Repair: Due to the complexity of the AIRMATIC system, professional diagnosis and repair are highly recommended. Specialized tools are often required. A good resource for understanding Mercedes-Benz suspension systems is official service manuals.

2. Transmission Shifting Problems

The powerful engines in the GL-Class are paired with sophisticated automatic transmissions, typically the 7G-TRONIC or 9G-TRONIC. While designed for seamless operation, some instances of rough shifting or hesitation can occur.

Symptoms:
Jerky or noticeable shifts between gears.
Hesitation when accelerating from a stop or a slow speed.
Delayed engagement of gears (e.g., when shifting from Park to Drive).
Transmission warning lights.

Causes:
Low transmission fluid level or degraded fluid quality.
Issues with the transmission control module (TCM) or its software.
Wear in the valve body or solenoids within the transmission.

Troubleshooting & Solutions:
Fluid Check & Change: The first step is to check the transmission fluid level and condition. If it’s low or dirty, a fluid and filter change according to Mercedes-Benz specifications is essential. This procedure is often best left to a qualified technician.
Software Update: Mercedes-Benz often releases software updates for the TCM to improve shifting logic and performance. Check with a dealer or reputable independent Mercedes specialist for available updates.
Sensor/Solenoid Diagnosis: If fluid and software are not the issue, a technician will need to diagnose sensors or solenoids within the transmission.
Professional Assessment: Transmission issues can be complex. It’s crucial to have a Mercedes-Benz specialist diagnose and repair any significant shifting problems.

3. Infotainment System Glitches

The COMAND infotainment system in the 2017 GL-Class offers navigation, entertainment, and vehicle settings. Like many advanced electronic systems, it can sometimes experience minor glitches.

Symptoms:
The screen freezing or becoming unresponsive.
Intermittent audio issues (crackling, no sound, distorted sound).
Navigation system becoming slow or inaccurate.
Bluetooth connectivity problems.
The system rebooting unexpectedly.

Causes:
Software bugs or conflicts.
Interference from other electronic devices.
Issues with connected USB drives or external media.
Power supply fluctuations.

Troubleshooting & Solutions:
System Reboot: A simple reboot can often resolve temporary glitches. This can sometimes be achieved by turning the car off, opening and closing the driver’s door, and restarting the engine.
Software Update: Similar to the transmission, the COMAND system can benefit from software updates from Mercedes-Benz.
Check Connections: Ensure all media devices and phone connections are stable and not causing interference.
Hard Reset (with caution): In some cases, a more involved reset might be possible, but this should only be performed if guided by a professional or detailed service manual.
Professional Diagnosis: For persistent or hardware-related issues, a visit to a Mercedes-Benz dealer or a qualified technician specializing in automotive electronics is recommended.

4. Water Pump and Coolant Leaks

The engine’s cooling system is vital. On some 2017 GL-Class models, particularly those with V6 or V8 engines, leaks from the water pump or associated coolant lines have been reported.

Symptoms:
Visible coolant leaks under the vehicle, often with a sweet smell.
The engine overheating or the temperature gauge rising too high.
Low coolant level warnings.
White residue or staining under the hood or around the engine.

Causes:
Degradation of seals and gaskets over time.
Corrosion on the water pump housing.
Cracks in plastic coolant reservoir tanks.

Troubleshooting & Solutions:
Immediate Action: If the engine overheats, pull over safely, turn off the engine, and allow it to cool completely before checking coolant levels. Do not drive with an overheating engine.
Coolant Level Check: Regularly check the coolant reservoir level when the engine is cold.
Visual Inspection: Look for any signs of leaks around the water pump, hoses, and radiator.
Component Replacement: If the water pump or a hose is leaking, it will need to be replaced. It’s often advisable to replace the thermostat and coolant at the same time if performing a water pump job.
Use Approved Coolant: Always use the correct type of Mercedes-Benz approved coolant for your vehicle to prevent corrosion and ensure proper performance. Your owner’s manual or a dealership can confirm the correct type. A helpful resource for automotive fluids is the API Engine Oil Licensing and Certification System documentation, which, while focused on oil, provides context on the importance of proper fluid specifications in vehicles.

5. Electrical System and Sensor Issues

Modern luxury vehicles like the GL-Class rely heavily on a complex network of sensors and electrical components. Occasionally, these can lead to various warning lights or system malfunctions.

Symptoms:
Various warning lights illuminating on the dashboard (e.g., check engine, ABS, ESP, airbag).
Intermittent issues with external lights (headlights, taillights).
Problems with power windows, seats, or mirrors.
Keyless entry or start system malfunctions.

Causes:
Faulty sensors (e.g., ABS wheel speed sensors, ambient temperature sensors).
Corroded electrical connectors or damaged wiring harnesses.
Issues with the alternator or battery.
Malfunctioning control modules.

Troubleshooting & Solutions:
Scan Tool Diagnosis: A crucial first step is to use an OBD-II scanner to retrieve diagnostic trouble codes (DTCs). Mercedes-Benz specific scanners provide more detailed information.
Inspect Batteries: Ensure the main battery and any auxiliary batteries are in good condition and properly charged. A failing battery can cause a cascade of electrical gremlins.
Inspect Connectors & Wiring: Look for visible signs of corrosion or damage to wiring harnesses and electrical connectors.
Component Testing: Individual sensors and modules will need to be tested by a qualified technician to determine if they are functioning correctly.
Professional Expertise: Due to the intricate nature of Mercedes-Benz electrical systems, professional diagnosis is often the most efficient and accurate approach.

2017 GL-Class Common Issues: A Closer Look

To better understand the reliability of the 2017 Mercedes-Benz GL-Class, let’s break down some of the specific components and potential concerns in a more structured way.

Technical Specifications and Potential Vulnerabilities

The 2017 GL-Class was available primarily with V6 and V8 gasoline engines, paired with automatic transmissions. Its advanced chassis and electronic systems contribute to its luxury and performance but also present areas where complexity can lead to specific needs.

Maintenance Milestones and Proactive Care

Adhering to the recommended maintenance schedule is paramount for the long-term reliability of any Mercedes-Benz, including the 2017 GL-Class. Key maintenance items that can prevent many common issues include:

Engine Oil and Filter Changes: Performed at Mercedes-Benz recommended intervals (typically every 10,000 miles or annually).
Transmission Fluid and Filter Service: Crucial for smooth shifting and longevity. Intervals depend on driving conditions, but a proactive change around 60,000-80,000 miles is often wise.
Coolant Flush and Replacement: Helps prevent corrosion and overheating.
Brake Fluid Flush: Ensures optimal braking performance and prevents corrosion in the brake system.
AIRMATIC System Check: If equipped, regular checks for leaks and proper function are recommended, especially around 50,000 to 80,000 miles.
Spark Plugs and Ignition Coils: Recommended replacement typically around 60,000-100,000 miles, depending on the engine and specific requirements.

For detailed information on your specific model’s maintenance schedule, always refer to the owner’s manual. You can often find digital versions of Mercedes-Benz owner’s manuals on the manufacturer’s official website.

Frequently Asked Questions About the 2017 Mercedes GL-Class

Here are some common questions new and existing owners of the 2017 Mercedes-Benz GL-Class might have:

Q1: Is the 2017 Mercedes GL-Class a reliable vehicle?

A1: Yes, the 2017 GL-Class is generally considered a reliable luxury SUV. It benefits from Mercedes-Benz’s robust engineering and high-quality materials. While there are a few common issues that can arise, they are typically manageable with proper maintenance and timely attention.

Q2: What are the most common problems with the 2017 GL-Class?

A2: The most frequently reported issues tend to involve the AIRMATIC suspension (air leaks, compressor), transmission shifting irregularities, occasional infotainment glitches, potential water pump leaks, and general electrical sensor issues.

Q3: How often should I change the transmission fluid in my 2017 GL-Class?

A3: Mercedes-Benz often has a “condition-based service” interval, but a proactive transmission fluid and filter change is generally recommended around 60,000 to 80,000 miles to ensure optimal performance and longevity.

Q4: What kind of maintenance does the AIRMATIC suspension require?

A4: The AIRMATIC system benefits from regular visual inspections for leaks in the air lines and bags. It’s also important to ensure the air compressor’s air dryer unit is serviced as per the maintenance schedule. Addressing any suspension sag or unusual noises promptly is key to preventing more serious issues.

Q5: Are parts for the 2017 GL-Class expensive to repair?

A5: As with most luxury German vehicles, parts and labor for Mercedes-Benz vehicles can be more expensive than for non-luxury brands. However, proactive maintenance can significantly reduce the frequency of costly repairs. Using quality aftermarket parts or finding a trusted independent Mercedes specialist can also help manage costs.

Q6: What is the typical lifespan of a 2017 GL-Class?

A6: With diligent maintenance and timely repairs, a 2017 Mercedes-Benz GL-Class can comfortably last well over 150,000 to 200,000 miles, and often much more. The engine and transmission are robustly built, and the interior holds up well over time.

Steps to Prevent Common Issues

Preventing potential problems is always better than fixing them. Here’s a proactive approach:

Adhere Strictly to the Maintenance Schedule: This is the most critical step. Follow the service intervals outlined in your owner’s manual for oil changes, fluid flushes, filter replacements, and component inspections.
Use High-Quality Fluids and Parts: Always use Mercedes-Benz approved fluids (oil, coolant, brake fluid) and genuine or high-quality OEM equivalent parts. This ensures compatibility and optimal performance. For instance, using the correct transmission fluid type is essential.
Listen for Unusual Sounds: Pay attention to any new noises from the engine, suspension, or exhaust. Hissing from the suspension, clunks, or whining sounds can be early indicators of issues.
Monitor Warning Lights: Never ignore dashboard warning lights, even if the vehicle seems to be driving normally. These lights are indicators of underlying problems that need diagnosis.
Address Leaks Promptly: Any visible fluid leaks under the vehicle should be investigated immediately. Even small coolant or oil leaks can be precursors to larger problems.
Keep Software Updated: Regularly check with your dealer or a specialist about any available software updates for the engine control module (ECM), transmission control module (TCM), and infotainment system.
Regular Professional Inspections: Beyond scheduled maintenance, consider an annual inspection, especially if you’re experiencing minor quirks or are approaching a significant mileage milestone.

Conclusion: Unbelievable Reliability, With a Touch of Vigilance

The 2017 Mercedes-Benz GL-Class (or GLS, as it became known) stands as a remarkable example of luxury SUV engineering, offering owners an exceptional combination of comfort, performance, and durability. The reputation for “unbelievable reliability” is well

Mercedes GL-Class 2017 Common Issues: Unbelievable Reliability

Your Guide to the 2017 Mercedes GL-Class: Understanding Its Reliability