# Mercedes-Benz 508 MOT reliability: pass rate and common failures | RegFlags

The Mercedes-Benz 508 passed its MOT first time 70% of the time, but from only 46 MOT tests, so treat it as a rough guide. See pass rates by year, common failures and typical mileage.

- First-time MOT pass rate: 70%
- MOT tests analysed: 46 (DVSA anonymised MOT data, 2025)
- Most common failure area: Brakes

These figures come from 46 MOT tests. That's a fairly small number of cars, so they may not be typical of these cars as a whole.

## By year of first use and fuel

| Year | Fuel | MOT tests | First-time pass rate |
| --- | --- | --- | --- |
| 2020 | Diesel | 2 (very few mots) | 50% |
| 2015 | Diesel | 1 (very few mots) | 100% |
| 2007 | Diesel | 1 (very few mots) | 0% |
| 1995 | Diesel | 1 (very few mots) | 100% |
| 1993 | Diesel | 2 (very few mots) | 100% |
| 1992 | Diesel | 1 (very few mots) | 100% |
| 1991 | Diesel | 2 (very few mots) | 0% |
| 1990 | Diesel | 3 (very few mots) | 67% |
| 1987 | Diesel | 18 (very few mots) | 67% |
| 1986 | Diesel | 5 (very few mots) | 80% |
| 1985 | Diesel | 5 (very few mots) | 80% |
| 1984 | Diesel | 1 (very few mots) | 100% |
| 1983 | Diesel | 1 (very few mots) | 100% |
| 1981 | Diesel | 1 (very few mots) | 100% |
| 1979 | Diesel | 2 (very few mots) | 50% |

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