2008 Mercedes-Benz R-Class — MOT failures & pass rate
2,001 MOT tests on the 2008 Mercedes-Benz R-Class are in this dataset, and 78.5% of them passed. That is 6.6 percentage points better than MPVs of a similar age, which fail at 28.1%. Failures cluster in brakes, lighting & signalling and emissions & environmental.
What the MOT record shows
No single area dominates — brakes (11.1%) and lighting & signalling (11.1%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are position lamp, rigid brake pipes and joints — position lamp alone was recorded 103 times.
Mileage matters less than usual here: the 2008 R-Class fails 19.2% of the time in the 30-60k band and 21.1% at 150k+, a spread of only 2.0 points.
Advisories point at the next bill rather than this one: brakes was flagged on 35.3% of tests without failing them.
The trend is improving — the fail rate fell from 22.7% in 2021 to 19.7% in 2025, as the worst-kept examples leave the fleet.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Brakes | 11.1% | 223 |
| 2 | Lighting & signalling | 11.1% | 223 |
| 3 | Emissions & environmental | 5.8% | 116 |
| 4 | Body, structure & corrosion | 4.3% | 86 |
| 5 | Tyres | 4.1% | 82 |
| 6 | Suspension | 3.8% | 75 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Position lamp | 103 |
| 2 | Rigid brake pipes | 79 |
| 3 | Joints | 74 |
| 4 | Rbt (sp) | 56 |
| 5 | Headlamp aim | 52 |
| 6 | Tread depth | 51 |
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 | 35.3% | 706 |
| 2 | Emissions & environmental | 29.5% | 590 |
| 3 | Tyres | 22.8% | 456 |
| 4 | Suspension | 17.6% | 352 |
| 5 | Body, structure & corrosion | 14.6% | 293 |
| 6 | Lighting & signalling | 8.8% | 177 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 30-60k | 73 | 19.2% |
| 60-90k | 302 | 18.9% |
| 90-120k | 584 | 22.3% |
| 120-150k | 612 | 22.9% |
| 150k+ | 416 | 21.1% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 1,935 | 21.7% |
| Petrol | 66 | 15.2% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 541 | 22.7% |
| 2022 | 479 | 23.0% |
| 2023 | 410 | 20.7% |
| 2024 | 312 | 19.6% |
| 2025 | 259 | 19.7% |
What to check before buying a 2008 R-Class
On a 2008 R-Class, brakes is what the MOT record says goes wrong most — it appeared in 11.1% of tests. Check these areas before you commit.
- Brakes (11.1% 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.
- Lighting & signalling (11.1% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Emissions & environmental (5.8% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
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 2008 Mercedes-Benz R-Classs pass their MOT?
78.5% of the 2,001 2008 Mercedes-Benz R-Class MOT tests in this dataset passed — a 21.5% fail rate.
What is the most common MOT failure on a 2008 Mercedes-Benz R-Class?
Brakes, recorded in 11.1% of tests, followed by lighting & signalling (11.1%).
Does the 2008 R-Class get worse with mileage?
Its MOT fail rate rises from 19.2% in the 30-60k band to 21.1% in the 150k+ band.
Methodology & source. Based on 2,001 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.