What breaks most · 2017 to 2021 model years
Mercedes-Benz GLS450 problems by year
Owners have filed 70 safety complaints with NHTSA about the Mercedes-Benz GLS450 across model years 2017 to 2021. Three years stand out: 2017 for electrical system complaints, 2021 for electrical system complaints and 2019 for speed control and throttle complaints.
- Years to check closely: 2017, 2021, 2019
- Complaints on file
- 702017 to 2021, all trims
- Worst year
- 201735 complaints
- Crashes reported
- 38 fires · 5 injuries · 0 deaths
- Typical failure mileage
- 13kMedian where owners gave mileage
- Recall campaigns
- 24Across the years shown
Complaints by model year
Raw filings with NHTSA, not adjusted for how many were sold.
| Model year | Complaints | Crashes | Recalls | Most-reported component |
|---|---|---|---|---|
| 35 | 1 | 8 | Electrical system (8) | |
| 4 | 1 | 2 | Speed control and throttle (1) | |
| 1 | 0 | 2 | Fuel system (1) | |
| 30 | 1 | 12 | Electrical system (14) |
What fails on the 2017 Mercedes-Benz GLS450
| Component | Share of complaints | Filings | Crashes | Parts for this job |
|---|---|---|---|---|
| Electrical systemAlternators, starters and ignition | 23% |
8 | 0 | Shop electrical system parts for the 2017 Mercedes-Benz GLS450 |
| EngineEngine gaskets and seals | 23% |
8 | 0 | Shop engine parts for the 2017 Mercedes-Benz GLS450 |
| Unknown or other | 20% |
7 | 0 | — |
| Exterior lightingHeadlights, tail lights and bulbs | 17% |
6 | 0 | Shop exterior lighting parts for the 2017 Mercedes-Benz GLS450 |
| Fuel systemFuel pumps and injectors | 14% |
5 | 0 | Shop fuel system parts for the 2017 Mercedes-Benz GLS450 |
| SteeringPower steering pumps, racks and hoses | 11% |
4 | 0 | Shop all steering parts, not filtered to this vehicle |
| SuspensionStruts, springs and control arms | 6% |
2 | 0 | Shop suspension parts for the 2017 Mercedes-Benz GLS450 |
| Seats | 6% |
2 | 0 | — |
One complaint can name more than one component, so shares add to more than 100%. "Unknown or other" is NHTSA's uncategorized bucket and is shown but never ranked.
In owners' words
Complaint narratives as filed with NHTSA, trimmed for length.
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Car destroyed by fire on March 19, 2023 while at a quick stop near Chickasaw, OK. Car was last serviced by Mercedes-Benz of Oklahoma City in December 2022. No personal injuries just a total loss of the vehicle. Cause of the fire at present is unknown. Pictures are available.
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1. Unknown, smoke started coming from under the passenger side seat, car is a complete loss. 2. Smoke damaged my lungs, there was a large amount of exploding glass, and it could have led to a structure fire. 3. Not applicable 4. In process, but it was recalled for this issue 5. No
How to read this page
Every figure comes from the National Highway Traffic Safety Administration's public complaint database, which holds every safety-related defect complaint filed by owners since 1995. We refresh it monthly and count each complaint once per component it names. Data through September 6, 2026.
NHTSA only accepts safety-related complaints. Rattles, paint, infotainment bugs and other annoyances are under-reported here, so this page is a map of what fails in ways owners consider dangerous, not a full reliability score.
Counts are raw. Use the year-over-year shape and the component mix, not the absolute numbers. Where a component maps to parts we stock, the row links to that category filtered to the year you are viewing. Air bag and seat belt complaints link to the recall checker instead, because those repairs are almost always covered.
Common questions
Which Mercedes-Benz GLS450 years have the most problems?
By NHTSA complaint volume, 2017, 2021, 2019 carry the most filings on the Mercedes-Benz GLS450. The 2017 alone has 35 complaints, led by electrical system.
What is the most common Mercedes-Benz GLS450 problem?
On the 2017 model year, the most-reported component is electrical system with 8 complaints. The table above lists the top components for every year.
At what mileage do Mercedes-Benz GLS450 problems start?
The median mileage at failure across all Mercedes-Benz GLS450 complaints that include mileage is about 13,000 miles. Older model years skew higher; the per-year figure is in the "at a glance" card.
Are these complaints verified?
No. NHTSA publishes complaints as submitted and does not investigate individual filings. Patterns across hundreds of complaints are meaningful; a single one is not.