Audi A6 vs Mercedes-Benz C-Class

On MOT-testable defects, the Audi A6 (fail rate 15.0%) performed better than the Mercedes-Benz C-Class (17.9%) across comparable years. The biggest divergence was suspension, where the C-Class recorded failures more often.

15.0%
A6 fail rate
17.9%
C-Class fail rate
2.95pp
Difference

Side by side

MOT figures compared
MetricAudi A6Mercedes-Benz C-Class
MOT tests analysed715,3232,277,625
Pass rate85.0%82.1%
Fail rate15.0%17.9%
Fail rate compared (lower is better) Audi A6 15.0% Mercedes-Benz C-Class 17.9%
Overall MOT fail rate across comparable model years.

Where they differ

Failure-area share, by category
CategoryA6C-Class
Suspension4.8%8.1%
Brakes2.7%5.4%
Emissions & environmental2.3%2.9%
Lighting & signalling5.8%5.5%
Tyres6.2%6.4%

Methodology & source. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.

See the full data