Bmw Z4 vs Mercedes-Benz Clk

On MOT-testable defects, the Bmw Z4 (fail rate 17.1%) performed better than the Mercedes-Benz Clk (25.3%) across comparable years. The biggest divergence was suspension, where the Clk recorded failures more often.

17.1%
Z4 fail rate
25.3%
Clk fail rate
8.26pp
Difference

Side by side

MOT figures compared
MetricBmw Z4Mercedes-Benz Clk
MOT tests analysed203,942204,964
Pass rate82.9%74.7%
Fail rate17.1%25.3%
Fail rate compared (lower is better) Bmw Z4 17.1% Mercedes-Benz Clk 25.3%
Overall MOT fail rate across comparable model years.

Where they differ

Failure-area share, by category
CategoryZ4Clk
Suspension5.7%14.7%
Lighting & signalling5.4%11.2%
Brakes4.8%8.2%
Tyres5.1%6.1%
Visibility3.3%4.2%

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