Audi A6 vs Mercedes-Benz C-Class
The Audi A6 has the better MOT record of the two — 14.7% fail rate versus 17.9% for the Mercedes-Benz C-Class across comparable years. The biggest single difference is suspension, where the C-Class records failures noticeably more often.
14.7%
A6 fail rate
17.9%
C-Class fail rate
3.21pp
Difference
Side by side
| Metric | Audi A6 | Mercedes-Benz C-Class |
|---|---|---|
| MOT tests analysed | 739,365 | 2,277,625 |
| Pass rate | 85.3% | 82.1% |
| Fail rate | 14.7% | 17.9% |
Where they differ
| Category | A6 | C-Class |
|---|---|---|
| Suspension | 4.7% | 8.1% |
| Brakes | 2.7% | 5.4% |
| Emissions & environmental | 2.3% | 2.9% |
| Tyres | 6.2% | 6.4% |
| Lighting & signalling | 5.6% | 5.5% |
Methodology & source. 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.