2021 Mercedes-Benz Gls Reliability ReportCommon Problems, Repair Costs & Expert Verdict
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Quick Facts · 2021 Mercedes-Benz Gls
- No active NHTSA safety recalls on record — a clean recall slate for the 2021 model year.
- Scores 4 points below the strongest nearby year — the 2022 Mercedes-Benz Gls earns a 82.
- The system most likely to surface first: electrical/infotainment system (mbux) (moderate severity).
The 2021 Mercedes-Benz Gls at a glance
- Is the 2021 Mercedes-Benz Gls reliable?
- Autojunket rates the 2021 Mercedes-Benz Gls 78/100 (grade B-), categorized as moderate risk. A supremely luxurious and capable SUV, but its advanced technology and systems carry a notable financial risk for long-term ownership.
- Should I buy a used 2021 Mercedes-Benz Gls?
- Autojunket recommends reading the full reliability report before buying a 2021 Mercedes-Benz Gls. The 2021 Mercedes-Benz GLS is a phenomenal luxury SUV offering an unmatched ownership experience for those who can afford it. However, its complex technology and intricate systems mean it is not for the faint of heart financially. If you have deep pockets, value cutting-edge luxury, and are prepared for potentially…
- Which Mercedes-Benz Gls years are the most reliable?
- Best model years to buy: 2022-present (minor refinements to MBUX and fewer early production quirks).. Years to avoid: None specifically, but early production examples of new generations (like the V167) always carry a slightly higher risk of initial glitches..
- What are the most common problems with the 2021 Mercedes-Benz Gls?
- The top failure points on the 2021 Mercedes-Benz Gls are Electrical/Infotainment System (MBUX) (typically around 15,000-45,000 miles), 48V Mild-Hybrid System (EQ Boost) (typically around 40,000-80,000 miles), AIRMATIC/E-ACTIVE BODY CONTROL Suspension (typically around 50,000-90,000 miles). Autojunket's full report includes repair-cost ranges and inspection checklists for each.
- At what mileage do problems start on the 2021 Mercedes-Benz Gls?
- The first major mileage danger zone for the 2021 Mercedes-Benz Gls is around 30,000. Initial Check-up Zone — At this mileage, most issues would be initial manufacturing defects or software glitches. Focus on ensuring all MBUX functions are stable and there are no persistent warning lights.
Every answer is generated from real repair, recall, and ownership data — full breakdown in the report.
Read the full free reportShould You Buy the 2021 Mercedes-Benz Gls?
The 2021 Mercedes-Benz GLS is a masterclass in luxury, technology, and comfort, making it a highly desirable full-size SUV. While generally well-engineered, its cutting-edge features and complex systems introduce a moderate risk of expensive repairs, particularly related to its advanced electronics and sophisticated air suspension. This vehicle demands a robust maintenance budget and a tolerance for occasional high-tech quirks to ensure long-term satisfaction.
The 2021 Mercedes-Benz GLS is a phenomenal luxury SUV offering an unmatched ownership experience for those who can afford it. However, its complex technology and intricate systems mean it is not for the faint of heart financially. If you have deep pockets, value cutting-edge luxury, and are prepared for potentially…
Best Model Years
2022-present (minor refinements to MBUX and fewer early production quirks).
Years to Avoid
None specifically, but early production examples of new generations (like the V167) always carry a slightly higher risk of initial glitches.
Biggest Strengths
- Exceptional build quality and luxurious materials
- Robust core powertrain components (engine, transmission)
- Advanced safety features and driver assistance systems
Top Risk Areas
The systems that tend to fail first on the 2021 Mercedes-Benz Gls, with the typical mileage window when each becomes a concern. Detailed repair-cost ranges and exact what-to-check inspection notes are in the full report.
Owners report issues with the MBUX system freezing, lagging, or requiring reboots. Sensor-related warnings (e.g., blind-spot assist, parking sensors) can also surface due to software glitches or minor component failures.
While not widespread for the 2021 model year, the integrated starter-generator (ISG) or its associated 48V battery has been a point of concern across Mercedes-Benz's EQ Boost lineup. Failures can lead to warning lights, reduced performan…
The standard air suspension, while offering an exceptional ride, comprises complex air springs, compressors, and control units. Leaks, sensor failures, or compressor wear can lead to a 'collapsed' suspension or error messages, resulting…
2021 Mercedes-Benz Gls Mileage Danger Zones
The mileage windows when the 2021 Mercedes-Benz Gls most commonly needs attention. Plan ahead, budget accordingly, and inspect before you cross each threshold.
Initial Check-up Zone
At this mileage, most issues would be initial manufacturing defects or software glitches. Focus on ensuring all MBUX functions are stable and there are no persistent warning lights.
Crucial Maintenance & Inspection Zone
This is a key mileage for major fluid services (transmission, differential, spark plugs on some engines) and a thorough inspection of the air suspension components. Neglecting these can shorten component life significantly.
Elevated Component Wear Zone
Expect potential wear-related failures for air suspension components, 48V system diagnostics, and possibly some ancillary engine sensors. Budget for potential higher repair costs.
High Risk & Major Investment Zone
Beyond 100k, the likelihood of major component failures for the air suspension, 48V system, and advanced electronics increases substantially. This is where diligent maintenance history truly pays off, but significant repairs become more…
2021 Mercedes-Benz Gls Ownership Cost Outlook
What it typically costs to keep the 2021 Mercedes-Benz Gls on the road. Full 5-year cost-of-ownership projection and major-failure-risk forecast are in the report.
Annual Maintenance
$800-1,500 (basic service, oil changes, cabin filters)
Moderate Repairs
$1,000-3,000 occasionally (e.g., MBUX module, sensor package, brake overhaul, minor air suspension part)
How Long Does the 2021 Mercedes-Benz Gls Last?
Proactive and meticulous scheduled maintenance is paramount for the 2021 GLS. Adhere strictly to Mercedes-Benz's service intervals, and always address any warning lights promptly, as delaying can lead to significantly more expensive cascade failures.
What 2021 Mercedes-Benz Gls Owners Actually Say
What Owners Love
- Unparalleled ride comfort and quietness, even on poor roads.
- Luxurious and meticulously crafted interior with premium materials.
- Powerful engine options provide effortless acceleration.
- Advanced MBUX infotainment system offers extensive features and personalization.
Common Frustrations
- High purchase price and even higher maintenance/repair costs.
- MBUX system can be complex to learn and prone to occasional glitches.
- Fuel economy is modest, especially with the V8 engine.
- Some owners find the dealer service experience to be expensive and occasionally inconsistent.
Who Should Buy the 2021 Mercedes-Benz Gls?
Best For
- Affluent families prioritizing ultimate comfort, space, and safety.
- Luxury enthusiasts who appreciate cutting-edge technology and refinement.
- Buyers seeking a powerful and prestigious long-distance cruiser.
Not Ideal For
- Budget-conscious buyers looking for low long-term running costs.
- DIY mechanics or those who prefer simpler, less complex vehicles.
How the 2021 Mercedes-Benz Gls Compares to Rivals
The 2021 GLS stands out for its blend of luxury, cutting-edge technology, and driving refinement. It generally surpasses American competitors in sophistication and some European rivals in pure comfort, but it does not match the simplistic, often lower-cost reliability of a Lexus.
More Reliable Than
- Cadillac Escalade (in terms of driving dynamics, interior refinement, and advanced tech integration)
- Lexus GX (in terms of modern technology, on-road comfort, and overall luxury experience)
Comparable To
- BMW X7 (very similar in terms of luxury, technology, and potential for high repair costs)
- Audi Q7/Q8 (offers similar tech and luxury but GLS is physically larger and often more comfortable)
NHTSA Recalls
No active NHTSA safety recalls on file for the 2021 Mercedes-Benz Gls. Always verify with your VIN atnhtsa.gov.
What breaks on the 2021 Mercedes-Benz Gls?
Full reliability breakdown — engine, transmission, rust, electrical. With repair costs and mileage danger zones.
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Mercedes-Benz Gls by Year
Compare AutoScores across nearby years of the Mercedes-Benz Gls. Click any year for its full report.
If You're Considering This, Also Look At
Similar class, similar year range — ranked by AutoScore.
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Where the 2021 Mercedes-Benz Gls report beats Carfax + CR
Carfax tells you if it crashed. Consumer Reports rates the whole nameplate. Autojunket tells you what will actually break on this specific year — and how to negotiate it.
Year-specific reliability score
Common problems + repair costs
Mileage danger zone map
AI negotiation script + walk-away price
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Frequently Asked Questions
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