2010 Mercedes-Benz SLK — MOT failures & pass rate
The 2010 Mercedes-Benz SLK passed 79.3% of its 12,840 recorded MOT tests. Coupes & convertibles of a similar age fail 19.2% of the time, so this is 1.5pp worse than the group it competes with. Failures cluster in suspension, lighting & signalling and brakes.
What the MOT record shows
Suspension dominates the failure mix at 11.6% of all tests — 5.0 points clear of lighting & signalling, so it is the first thing to check.
At component level the recurring items are coil spring, ball joint and rigid brake pipes — coil spring alone was recorded 1,037 times.
Condition tracks the odometer closely. Failures run at 11.3% in the 0-30k band and 33.6% in the 150k+ band, a 22.3-point spread — more than double.
Advisories point at the next bill rather than this one: brakes was flagged on 26.1% of tests without failing them.
The trend is worsening — 19.6% of tests failed in 2021 against 21.7% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Suspension | 11.6% | 1,488 |
| 2 | Lighting & signalling | 6.6% | 851 |
| 3 | Brakes | 5.2% | 669 |
| 4 | Tyres | 4.9% | 629 |
| 5 | Emissions & environmental | 1.8% | 232 |
| 6 | Visibility | 1.6% | 199 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Coil spring | 1,037 |
| 2 | Ball joint | 525 |
| 3 | Rigid brake pipes | 407 |
| 4 | Individual direction indicators | 400 |
| 5 | Tread depth | 319 |
| 6 | Headlamp aim | 229 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Brakes | 26.1% | 3,345 |
| 2 | Tyres | 22.8% | 2,923 |
| 3 | Suspension | 15.8% | 2,023 |
| 4 | Lighting & signalling | 7.9% | 1,020 |
| 5 | Body, structure & corrosion | 5.1% | 660 |
| 6 | Other defects | 4.7% | 606 |
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 | 1,027 | 11.3% |
| 30-60k | 5,394 | 18.1% |
| 60-90k | 4,560 | 23.0% |
| 90-120k | 1,383 | 27.2% |
| 120-150k | 327 | 27.8% |
| 150k+ | 146 | 33.6% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 2,604 | 19.6% |
| 2022 | 2,583 | 20.0% |
| 2023 | 2,572 | 20.5% |
| 2024 | 2,589 | 21.9% |
| 2025 | 2,492 | 21.7% |
What to check before buying a 2010 SLK
On a 2010 SLK, suspension is what the MOT record says goes wrong most — it appeared in 11.6% of tests. Check these areas before you commit.
- Suspension (11.6% 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.
- Lighting & signalling (6.6% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Brakes (5.2% 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 many 2010 Mercedes-Benz SLKs pass their MOT?
79.3% of the 12,840 2010 Mercedes-Benz SLK MOT tests in this dataset passed — a 20.7% fail rate.
What is the most common MOT failure on a 2010 Mercedes-Benz SLK?
Suspension, recorded in 11.6% of tests, followed by lighting & signalling (6.6%).
Does the 2010 SLK get worse with mileage?
Its MOT fail rate rises from 11.3% in the 0-30k band to 33.6% in the 150k+ band.
Methodology & source. Based on 12,840 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.