2006 Mercedes-Benz Sl — MOT failures & pass rate
4,722 MOT tests on the 2006 Mercedes-Benz Sl are in this dataset, and 85.4% of them passed. Against coupes & convertibles of a similar age (22.0% fail rate), the 2006 Sl comes out 7.4pp better. Failures cluster in suspension, brakes and tyres.
What the MOT record shows
No single area dominates — suspension (6.6%) and brakes (4.0%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are coil spring, ball joint and rigid brake pipes — coil spring alone was recorded 166 times.
Condition tracks the odometer closely. Failures run at 6.9% in the 0-30k band and 19.4% in the 150k+ band, a 12.5-point spread — more than double.
Advisories point at the next bill rather than this one: brakes was flagged on 24.1% of tests without failing them.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Suspension | 6.6% | 312 |
| 2 | Brakes | 4.0% | 189 |
| 3 | Tyres | 3.8% | 177 |
| 4 | Lighting & signalling | 3.0% | 140 |
| 5 | Visibility | 1.9% | 92 |
| 6 | Emissions & environmental | 1.6% | 74 |
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 | 166 |
| 2 | Ball joint | 114 |
| 3 | Rigid brake pipes | 81 |
| 4 | Tread depth | 71 |
| 5 | Headlamp aim | 68 |
| 6 | Malfunction indicator lamp | 64 |
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 | 24.1% | 1,139 |
| 2 | Tyres | 19.0% | 896 |
| 3 | Suspension | 14.2% | 671 |
| 4 | Other defects | 5.7% | 267 |
| 5 | Emissions & environmental | 5.1% | 239 |
| 6 | Lighting & signalling | 3.8% | 180 |
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 | 260 | 6.9% |
| 30-60k | 1,474 | 11.3% |
| 60-90k | 1,725 | 16.1% |
| 90-120k | 923 | 18.5% |
| 120-150k | 241 | 15.3% |
| 150k+ | 98 | 19.4% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 1,003 | 14.4% |
| 2022 | 988 | 14.8% |
| 2023 | 953 | 13.6% |
| 2024 | 903 | 16.4% |
| 2025 | 875 | 13.9% |
What to check before buying a 2006 Sl
On a 2006 Sl, suspension is what the MOT record says goes wrong most — it appeared in 6.6% of tests. Check these areas before you commit.
- Suspension (6.6% 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.
- Brakes (4.0% 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.
- Tyres (3.8% 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.
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 2006 Mercedes-Benz Sls pass their MOT?
85.4% of the 4,722 2006 Mercedes-Benz Sl MOT tests in this dataset passed — a 14.6% fail rate.
What is the most common MOT failure on a 2006 Mercedes-Benz Sl?
Suspension, recorded in 6.6% of tests, followed by brakes (4.0%).
Does the 2006 Sl get worse with mileage?
Its MOT fail rate rises from 6.9% in the 0-30k band to 19.4% in the 150k+ band.
Methodology & source. Based on 4,722 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.