AutoUtility currently tracks 37 official NHTSA owner defect complaints for the 2021 Mercedes-Benz GLS. Electrical System issues are the most frequently reported category, appearing in 17 complaints (45.9% of submitted records). Among these NHTSA complaint records, 2 filings cite a crash, 2 cite a fire, 3 report one or more injuries. The 2021 Mercedes-Benz GLS belongs to the 3rd Generation (X167) platform.
Factual proportion of owner complaints categorized by automotive subsystem in NHTSA records
17 owner complaints submitted to NHTSA ODI for this subsystem.
5 owner complaints submitted to NHTSA ODI for this subsystem.
5 owner complaints submitted to NHTSA ODI for this subsystem.
2 owner complaints submitted to NHTSA ODI for this subsystem.
Representative defect filings submitted by owners to the NHTSA Office of Defects Investigation
"The vehicle suffered a sudden, catastrophic 48V mild-hybrid electrical power supply breakdown and complete system failure while traveling at highway speeds during a cross-country move. The sudden failure forced an emergency lane change into an isolation zone just off the highway. The sudden failure..."
"48V battery has repeated failures where I'm driving. safety concern, When it fail, it will pop up warning1) only drive below 50 miles/hour; then it becomes2) stop vehicle immediately; then ) multi-media system suddenly shut off while I'm driving. I tested by 48V battery which only has below 60%..."
"The contact owns a 2021 Mercedes-Benz GLS580. The contact stated that after entering the vehicle, the contact became aware of an abnormally strong fuel odor inside the vehicle. There was no warning light illuminated. The vehicle was taken to two independent mechanics who referred the contact to the..."
"Both rear wheels on this vehicle have developed cracks which leads to tire pressure loss. Apparently, this is a common issue with Mercedes' heavier vehicles like the GLS and S series sedans. To be clear, I did not hit anything. I did not do any unusual driving. Both rear tires are fine. While you..."
"On [XXX], I was heading home from work traveling [XXX] on [XXX] through Atlanta's usual heavy traffic. I smelled smoke inside my car and saw fire flames coming from under my passenger seat. My initial reaction was to try to put the fire out with my hat without burning myself. Also, I had to try to..."
Reported defect complaint volume across sibling model years (2017–2026)
| Model Year | NHTSA Complaints | Crash Reports | Safety Recalls | Detailed Report |
|---|---|---|---|---|
| 2017 Mercedes-Benz GLS | 41 | 1 | 8 | View 2017 Problems → |
| 2018 Mercedes-Benz GLS | 22 | 1 | 4 | View 2018 Problems → |
| 2019 Mercedes-Benz GLS | 27 | 1 | 3 | View 2019 Problems → |
| 2020 Mercedes-Benz GLS | 38 | 3 | 24 | View 2020 Problems → |
| 2021 Mercedes-Benz GLS Current Page | 37 | 2 | 12 | Current |
| 2022 Mercedes-Benz GLS | 15 | 2 | 10 | View 2022 Problems → |
| 2023 Mercedes-Benz GLS | 10 | 0 | 5 | View 2023 Problems → |
| 2024 Mercedes-Benz GLS | 0 | 0 | 0 | View 2024 Problems → |
| 2025 Mercedes-Benz GLS | 0 | 0 | 0 | View 2025 Problems → |
| 2026 Mercedes-Benz GLS | 0 | 0 | 0 | View 2026 Problems → |
Complete distribution of consumer defect reports across all 18 granular NHTSA system and subsystem classifications
| Vehicle Component / System | Total Complaints | Crash Reports | Fire Reports | Injury Entries | Fatality Entries |
|---|---|---|---|---|---|
| Electrical System NHTSA category: ELECTRICAL SYSTEM | 10 | 0 | 0 | 0 | 0 |
| Other / Uncategorized NHTSA category: UNKNOWN OR OTHER | 6 | 1 | 0 | 1 | 0 |
| ELECTRICAL SYSTEM,ENGINE | 2 | 0 | 0 | 1 | 0 |
| ELECTRICAL SYSTEM,SEATS | 2 | 0 | 2 | 0 | 0 |
| Fuel System NHTSA category: FUEL SYSTEM, GASOLINE | 2 | 0 | 0 | 0 | 0 |
| Lane Departure Warning NHTSA category: LANE DEPARTURE | 2 | 0 | 0 | 0 | 0 |
| Visibility & Wipers NHTSA category: VISIBILITY/WIPER | 2 | 0 | 0 | 0 | 0 |
| Air Bags NHTSA category: AIR BAGS | 1 | 1 | 0 | 1 | 0 |
| ELECTRICAL SYSTEM,UNKNOWN OR OTHER | 1 | 0 | 0 | 0 | 0 |
| ENGINE,FORWARD COLLISION AVOIDANCE,LANE DEPARTURE | 1 | 0 | 0 | 0 | 0 |
| Forward Collision Avoidance NHTSA category: FORWARD COLLISION AVOIDANCE | 1 | 0 | 0 | 0 | 0 |
| POWER TRAIN,ELECTRICAL SYSTEM,ENGINE | 1 | 0 | 0 | 0 | 0 |
| Seat Belts NHTSA category: SEAT BELTS | 1 | 0 | 0 | 0 | 0 |
| SUSPENSION,ELECTRICAL SYSTEM,ENGINE | 1 | 0 | 0 | 0 | 0 |
| Tires NHTSA category: TIRES | 1 | 0 | 0 | 0 | 0 |
| UNKNOWN OR OTHER,STRUCTURE | 1 | 0 | 0 | 0 | 0 |
| VEHICLE SPEED CONTROL,FORWARD COLLISION AVOIDANCE | 1 | 0 | 0 | 0 | 0 |
| Wheels & Hubs NHTSA category: WHEELS | 1 | 0 | 0 | 0 | 0 |
Cross-reference safety recalls, crash test safety ratings, and EPA fuel economy for this model year
Key performance indicators, EPA fuel economy specs, powertrain variants, and summary ratings.
Official recall campaigns, safety defect descriptions, and manufacturer free remedy instructions.
NHTSA 5-Star NCAP crash test results, driver assistance systems, and rollover resistance ratings.
EPA fuel economy ratings, electric range, and annual energy cost benchmarks.
Direct, deterministic answers synthesized from verified United States government databases for the 2021 Mercedes-Benz GLS
In official NHTSA consumer records, the most frequently cited issue area for the 2021 Mercedes-Benz GLS is Electrical System, appearing in 17 records (45.9% of submitted filings).
Secondary reported categories include Engine & Cooling (5) and Driver Assistance & Safety Tech (5).
AutoUtility does not issue subjective reliability scores or commercial ratings. In official United States government records, NHTSA tracks 37 consumer defect complaints and 12 safety recall campaigns for the 2021 Mercedes-Benz GLS.
Reviewing documented component complaint distributions, recall remedy notices, and active federal investigations provides an objective, evidence-based view of the vehicle's historical safety and defect record.
Among consumer complaint records on file with NHTSA for the 2021 Mercedes-Benz GLS, 2 filings cite a crash, 2 cite smoke or fire, and 3 report one or more injuries.
Incident entries represent consumer descriptions at the time of submission to federal authorities and do not establish mechanical causation or legal liability.
The complaint records on this page are retrieved directly from the NHTSA Office of Defects Investigation (ODI) public database under 49 CFR Part 576.
Local Production Store Compiled: August 2026 • Deterministic Audited Dataset • Zero Dynamic External API Runtime Latency.