2017 Mercedes-Benz S-Class — MOT failures & pass rate
Across 13,671 MOT tests, the 2017 Mercedes-Benz S-Class recorded a 90.7% pass rate. That is 2.2 percentage points better than executive cars of a similar age, which fail at 11.5%. Failures cluster in tyres, suspension and visibility.
What the MOT record shows
No single area dominates — tyres (4.8%) and suspension (2.6%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are ball joint, tread depth and washers — ball joint alone was recorded 414 times.
Mileage matters less than usual here: the 2017 S-Class fails 6.1% of the time in the 0-30k band and 6.6% at 150k+, a spread of only 0.6 points.
Fuel type barely separates them — petrol fails 8.2% of the time against 9.5% for diesel.
Tyres is the most common advisory, noted on 18.1% of tests — work that passed today but is likely due soon.
The trend is worsening — 8.0% of tests failed in 2021 against 10.4% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 4.8% | 649 |
| 2 | Suspension | 2.6% | 351 |
| 3 | Visibility | 1.4% | 190 |
| 4 | Brakes | 1.1% | 148 |
| 5 | Emissions & environmental | 1.0% | 140 |
| 6 | Lighting & signalling | 1.0% | 132 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Ball joint | 414 |
| 2 | Tread depth | 414 |
| 3 | Washers | 166 |
| 4 | Malfunction indicator lamp | 129 |
| 5 | Brake pads | 127 |
| 6 | Registration plates | 103 |
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 | 18.1% | 2,480 |
| 2 | Brakes | 10.4% | 1,426 |
| 3 | Suspension | 5.8% | 789 |
| 4 | Other defects | 3.1% | 418 |
| 5 | Visibility | 2.0% | 276 |
| 6 | Body, structure & corrosion | 0.6% | 88 |
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 | 3,085 | 6.1% |
| 30-60k | 5,211 | 11.4% |
| 60-90k | 2,682 | 10.9% |
| 90-120k | 1,231 | 7.8% |
| 120-150k | 704 | 7.0% |
| 150k+ | 754 | 6.6% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 10,510 | 9.5% |
| Petrol | 2,698 | 8.2% |
| Hybrid | 457 | 12.0% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 2,901 | 8.0% |
| 2022 | 2,887 | 8.5% |
| 2023 | 2,777 | 9.7% |
| 2024 | 2,613 | 10.2% |
| 2025 | 2,493 | 10.4% |
What to check before buying a 2017 S-Class
The failure pattern for this year is specific enough to inspect against: tyres accounted for 4.8% of tests. Start there.
- Tyres (4.8% 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 (2.6% 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.
- Visibility (1.4% of tests): Wipers, washers, mirrors and screen damage — usually inexpensive, but check for chips in the driver's line of sight. Typical repair: £15–£150.
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 many 2017 Mercedes-Benz S-Classs pass their MOT?
90.7% of the 13,671 2017 Mercedes-Benz S-Class MOT tests in this dataset passed — a 9.3% fail rate.
What is the most common MOT failure on a 2017 Mercedes-Benz S-Class?
Tyres, recorded in 4.8% of tests, followed by suspension (2.6%).
Does the 2017 S-Class get worse with mileage?
Its MOT fail rate rises from 6.1% in the 0-30k band to 6.6% in the 150k+ band.
Methodology & source. Based on 13,671 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-27. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.