What breaks most · 2018 to 2025 model years
Mercedes-Benz GLC 300 problems by year
Owners have filed 416 safety complaints with NHTSA about the Mercedes-Benz GLC 300 across model years 2018 to 2025. Three years stand out: 2018 for engine complaints, 2020 for engine complaints and 2021 for engine complaints. The quietest years are 2019, 2023 and 2022.
- Years to check closely: 2018, 2020, 2021
- Fewest complaints: 2019, 2023, 2022
- Complaints on file
- 4162018 to 2025, all trims
- Worst year
- 201887 complaints
- Crashes reported
- 237 fires · 18 injuries · 1 deaths
- Typical failure mileage
- 20kMedian where owners gave mileage
- Recall campaigns
- 74Across 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 |
|---|---|---|---|---|
| 87 | 4 | 12 | Engine (28) | |
| 46 | 4 | 12 | Electrical system (14) | |
| 69 | 3 | 16 | Engine (21) | |
| 63 | 1 | 9 | Engine (30) | |
| 59 | 5 | 2 | Steering (14) | |
| 55 | 2 | 12 | Electrical system (30) | |
| 21 | 1 | 8 | Engine (7) | |
| 16 | 3 | 3 | Electrical system (12) |
What fails on the 2018 Mercedes-Benz GLC 300
| Component | Share of complaints | Filings | Crashes | Parts for this job |
|---|---|---|---|---|
| EngineEngine gaskets and seals | 32% |
28 | 0 | Shop engine parts for the 2018 Mercedes-Benz GLC 300 |
| Unknown or other | 23% |
20 | 2 | — |
| Electrical systemAlternators, starters and ignition | 15% |
13 | 2 | Shop electrical system parts for the 2018 Mercedes-Benz GLC 300 |
| Body and structureDoors, latches and body hardware | 10% |
9 | 1 | Shop body and structure parts for the 2018 Mercedes-Benz GLC 300 |
| Seat belts | 9% |
8 | 0 | Check recalls for seat belts on NHTSA.gov |
| Powertrain and transmissionTransmission parts | 9% |
8 | 1 | Shop all powertrain and transmission parts, not filtered to this vehicle |
| Fuel systemFuel pumps and injectors | 8% |
7 | 0 | Shop fuel system parts for the 2018 Mercedes-Benz GLC 300 |
| Air bags | 7% |
6 | 0 | Check recalls for air bags on NHTSA.gov |
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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I have engine light on and when I scanned it, I got a error code P052E For crankcase vent valve issues. It is most common problem with Mercedes-Benz Glc .
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The check engine light was on. There is a problem with the oil pump valve of the engine. The problem has been confirmed by a dealer and an independent mechanic.
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Twice my car slowed down tremendously in traffic because of a bad cylinder head. I drive a 2021 Mercedes GLC 300 4matic with 33,529 miles. In reviewing other complaints, this is a common and known complaint. My check engine light came on and I could not go over 40 mph. This is very dangerous.
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 GLC 300 years have the most problems?
By NHTSA complaint volume, 2018, 2020, 2021 carry the most filings on the Mercedes-Benz GLC 300. The 2018 alone has 87 complaints, led by engine.
What is the most common Mercedes-Benz GLC 300 problem?
On the 2018 model year, the most-reported component is engine with 28 complaints. The table above lists the top components for every year.
At what mileage do Mercedes-Benz GLC 300 problems start?
The median mileage at failure across all Mercedes-Benz GLC 300 complaints that include mileage is about 20,000 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.