The Mercedes-Benz GL450, part of the GL-Class (X164 generation), represents full-size luxury SUV excellence with its blend of premium comfort, robust performance, and cutting-edge technology. However, potential buyers and current owners often ask: How reliable is the Mercedes-Benz GL450?
To help answer that question, we take a look at real-world reliability scores, common problems, maintenance costs, and expert opinions from places like J.D. Power, RepairPal, and NHTSA. Whether you’re looking at a used GL450 or have one already, this guide gives you important info about how dependable it really is over time.
Reliability Scores from Credible Sources
| Source | Reliability Score (Out of 100 or 5) | Category |
|---|---|---|
| J.D. Power | 76/100 | “Average” |
| Consumer Reports | 3/5 | “Fair” |
| RepairPal | 2.5/5 | “Below Average” |
| NHTSA Recalls | Multiple Recalls Reported | “Moderate Concerns” |
J.D. Power: 72/100 Reliability Rating
J.D. Power gives the GL450 a reliability rating of 76 out of 100. This puts it in the average range, about the same as rivals like the 2012 Cadillac Escalade and Lincoln Navigator but not quite as high as the Japanese models like the Infiniti QX56 or Lexus LX. People love it for its strong powertrain and smooth ride, but some owners have had trouble with electrical stuff and the air suspension.
RepairPal: 2.5/5 Rating
RepairPal says the GL450 doesn’t get a great score, pointing out that the annual repair costs come to about $1,314. That’s more than what you’d typically pay for luxury SUVs. Just to give you an idea, the 2012 Cadillac Escalade only costs $930 a year for maintenance, and the Infiniti is even lower at $828.
NHTSA Recalls and Safety Concerns
The National Highway Traffic Safety Administration (NHTSA) has reported three recalls for the X164 GL450, with two carrying a “Do Not Drive Warning“! This warning suggests that if the vehicle hasn’t received the necessary repairs, it could pose a serious safety risk.
- Brake Booster Corrosion May Impair Braking (April 2024)
- Brake Booster Corrosion May Impair Braking (May 2022)
- Driver’s Frontal Air Bag Inflator May Rupture (February 2016)
For more detailed information, including recall dates, please visit the NHTSA website or consult your local dealer.
Common Issues with the Mercedes-Benz GL450
Despite its luxurious appeal, the GL450 is known for several recurring issues. Below are the most commonly reported concerns:
1. Air Suspension Failures (AIRMATIC System)
- The GL450’s AIRMATIC air suspension provides a smooth ride but is prone to failure.
- Common symptoms include sagging suspension, compressor failure, and uneven ride height.
- Repairs can cost $1,500–$3,000, depending on components replaced.
2. Transmission & Transfer Case Problems
- Some owners report rough shifting, delayed gear engagement, and transmission jerking.
- The 7G-Tronic automatic transmission may require software updates or valve body repairs.
- Transfer case failures in 4MATIC models can lead to expensive drivetrain repairs ($2,500–$4,000).
3. Electrical Malfunctions
- Common complaints include faulty command system, keyless entry malfunctions, and battery drain.
- Some models experience ECU software glitches, affecting engine and transmission performance.
- Replacing wiring harnesses and sensors can cost $500–$1,500.
4. Engine Issues (M273 4.7L V8 & M278 4.6L Biturbo V8)
- Earlier M273 V8 engines (X164 generation, 2007-2012) suffered from timing chain wear and balance shaft failures.
- Later M278 twin-turbo V8 models (X166 generation, 2013-2019) had turbocharger oil seal leaks, leading to high repair costs ($3,000–$6,000).
5. Brake System & Steering Issues
- Premature brake wear is common, especially on heavy GL450 models.
- Power steering leaks and failures have been reported in high-mileage vehicles.
Maintenance and Ownership Costs
Owning a GL450 demands premium maintenance, given its complexity and luxury features. Below is an estimated breakdown of routine service costs:
| Service Type | Estimated Cost | Frequency |
| Oil Change | $150–$200 | Every 10,000 miles |
| Brake Pad Replacement | $350–$700 | Every 40,000 miles |
| Transmission Service | $400–$600 | Every 60,000 miles |
| AIRMATIC Suspension Repair | $1,500–$3,000 | As Needed |
| Engine Timing Chain Service | $3,000–$5,000 | 100,000+ miles |
Is the Mercedes-Benz GL450 Worth Buying?
Pros
✅ Luxury Interior & Ride Quality – Spacious cabin with premium materials.
✅ Strong Performance – Powerful V8 engines and solid towing capacity.
✅ Safety Features – Advanced driver aids and high crash-test ratings.
✅ Capable AWD System – 4MATIC offers excellent all-weather capability.
Cons
❌ Expensive Maintenance – Higher upkeep costs than non-luxury SUVs.
❌ Air Suspension Reliability – AIRMATIC failures can be costly.
❌ Electrical System Issues – Infotainment and sensor malfunctions common.
Final Verdict
The Mercedes-Benz GL450 is a really nice and luxurious SUV that packs a punch. It’s got great safety ratings and feels super comfy to ride in while also delivering solid performance. But be aware that owning one can be pricey, and its reliability is just okay since it tends to have issues with air suspension and electronics.
If you’re thinking about getting a used GL450, make sure you get a pre-purchase inspection (PPI) and ask for the full service history. The most dependable models will have had air suspension parts replaced, the ECU software updated, and regular maintenance done.
If you’re on the lookout for a reliable Mercedes SUV take a peek at this article “What Are The Best Used Mercedes-Benz SUVs? See The Top 3“. Explore more of our site for expert car reviews, in-depth buying guides, and the latest industry insights. There’s plenty to discover—take a look around and bookmark us for future updates!
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