Where each one leads
BMW Z4
- New BMW Z4 cars registered in Europe in 2022 average 170 g/km of CO₂ on the WLTP test, against 177 for the Mercedes-Benz SLC-Class in 2021.
Mercedes-Benz SLC-Class
- Fewer Mercedes-Benz SLC-Class cars in the Netherlands carry an illogical odometer record (3.0% against 4.2%).
Only measures that do not depend on how many cars were sold: pass and failure rates against cars of the same age, ratings, fuel use and CO₂. How we compare
At a glance
| BMW Z4 | Mercedes-Benz SLC-Class | |
|---|---|---|
| Model years in the US safety record | 2002–2025 | — |
| New cars registered in Europe | 60,724 (2010–2022) | 24,938 (2016–2021) |
| Licensed in the United Kingdom | 32,458 | 7,999 |
| On the road in the Netherlands | 5,299 | 340 |
| In traffic in Finland | 773 | — |
EEA new-car registrations (CC BY 4.0) · DVLA licensed vehicles (OGL v3.0) · RDW (CC0) · Traficom (CC BY 4.0) · generations: Wikidata (CC0).
Reliability and problems
| BMW Z4 | Mercedes-Benz SLC-Class | |
|---|---|---|
| UK MOT first-time pass rate | 77% | — |
| … against cars of the same age | +20% | — |
| New York safety inspections failed | 1.0% | — |
| … against cars of the same year | −51% | — |
| Illogical odometer records (NL) | 4.2% | 3.0% |
| US owner complaints | 1,282 | — |
| Most complaints about | Steering | — |
| Model year with most complaints | 2003 (414) | — |
| US recall campaigns | 28 | — |
| Manufacturer service bulletins | 1,817 | — |
| NHTSA defect investigations | 9 | — |
Complaint, recall and bulletin counts grow with the number of cars sold and are not adjusted for it. UK MOT: DVSA anonymised MOT results (OGL v3.0); New York: DMV inspections; complaints, recalls, bulletins and investigations: NHTSA (public domain); odometer: RDW (CC0).
Fuel, emissions and price
| BMW Z4 | Mercedes-Benz SLC-Class | |
|---|---|---|
| Official combined fuel use, Canada | 8.4 l/100 km (2026) | — |
| Real-world use in Europe, petrol | 8.9 l/100 km | — |
| Official CO₂ of new cars in Europe | 170 g/km | 177 g/km |
| Average power of new cars in Europe | 193 kW (259 hp) | 154 kW (206 hp) |
| Average mass in running order | 1,554 kg | 1,493 kg |
| Dutch list price when new (median) | €70,203 | €62,006 |
| Average odometer in Finland | 136,000 km | — |
Canada: NRCan Fuel Consumption Ratings, most frugal version of the latest year (OGL Canada). Europe: EEA monitoring of new-car CO₂ and on-board fuel meters (OBFCM), CC BY 4.0. Price: RDW catalogue price (CC0). Finland: Traficom (CC BY 4.0).