Mercedes-Benz GLC300d — MOT pass rate & failures
The Mercedes-Benz GLC300d recorded a 92.3% MOT pass rate across 30,245 tests in this dataset (model years 2019–2024), with tyres, suspension and brakes its most common failure areas. Its 7.7% fail rate is lower than the 9.4% average across all Mercedes-Benz GLC versions.
How it compares
By model year
| Year | Tests | Pass rate | Fail rate |
|---|---|---|---|
| 2019 | 8,337 | 92.2% | 7.8% |
| 2020 | 13,547 | 92.0% | 8.0% |
| 2021 | 5,630 | 92.4% | 7.6% |
| 2022 | 2,684 | 93.2% | 6.8% |
| 2023 | 44 | 100.0% | 0.0% |
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 5.1% | 1,537 |
| 2 | Suspension | 1.1% | 338 |
| 3 | Brakes | 1.1% | 335 |
| 4 | Visibility | 1.1% | 322 |
| 5 | Lighting & signalling | 0.8% | 252 |
| 6 | Other defects | 0.4% | 105 |
| 7 | Body, structure & corrosion | 0.2% | 57 |
| 8 | Emissions & environmental | 0.2% | 58 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Tread depth | 505 |
| 2 | Ball joint | 345 |
| 3 | Brake pads | 342 |
| 4 | Headlamp aim | 263 |
| 5 | Wipers | 203 |
| 6 | Registration plates | 174 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Tyres | 21.7% | 6,550 |
| 2 | Brakes | 9.1% | 2,741 |
| 3 | Other defects | 5.7% | 1,735 |
| 4 | Suspension | 3.6% | 1,083 |
| 5 | Visibility | 3.4% | 1,020 |
| 6 | Lighting & signalling | 0.4% | 112 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 0-30k | 11,883 | 5.9% |
| 30-60k | 15,367 | 8.6% |
| 60-90k | 2,620 | 10.3% |
| 90-120k | 310 | 12.3% |
| 120-150k | 48 | 14.6% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2022 | 2,156 | 5.4% |
| 2023 | 6,777 | 6.7% |
| 2024 | 9,496 | 8.2% |
| 2025 | 11,800 | 8.4% |
What to check before buying a Mercedes-Benz GLC300d
Focus on the areas it most often fails on — and remember MOT data covers testable defects only, not engine or gearbox health.
- Tyres (5.1% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
- Suspension (1.1% of tests): Worn drop links, bushes, springs or shocks — listen for knocks over bumps and check for uneven tyre wear. Typical repair: £150–£450 per corner.
- Brakes (1.1% of tests): Pads/discs are routine wear; binding, imbalance or corroded pipes are more serious — test for pulling under braking. Typical repair: £100–£350 per axle.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
How reliable is the Mercedes-Benz GLC300d at MOT time?
92.3% of the 30,245 Mercedes-Benz GLC300d MOT tests in this dataset passed — a 7.7% fail rate, better than the 9.4% average across all GLC versions.
What is the most common MOT failure on a Mercedes-Benz GLC300d?
Tyres, recorded in 5.1% of tests, followed by suspension (1.1%).
Does the GLC300d get worse with mileage?
Its MOT fail rate rises from 5.9% in the 0-30k band to 14.6% in the 120-150k band.
Methodology & source. Based on 30,245 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-06. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.