Show table of content Hide table of content
When a German premium manufacturer decides to source its latest gasoline engine from China, the automotive industry takes notice. Mercedes-Benz has chosen this path for the M252 powertrain, a 1.5-liter four-cylinder unit designed to power its upcoming compact models. This strategic decision raises fundamental questions about manufacturing philosophy, efficiency standards, and the future direction of combustion engines in an increasingly electrified landscape.
La plateforme FAME et les fondamentaux techniques du M252
The M252 engine belongs to the Family of Modular Engines platform, which serves as Mercedes’ foundation for next-generation thermal powertrains. This four-cylinder unit operates on a Miller cycle configuration, a thermodynamic variant that differs from the conventional Otto cycle by implementing higher compression ratios and earlier intake valve closure. This approach minimizes heat losses and maximizes overall efficiency, delivering tangible benefits in real-world consumption figures.
Mercedes offers three power outputs for this transversely-mounted block : 136, 163, and 190 horsepower. These versions target different market segments while maintaining remarkably low fuel consumption figures, with preliminary data indicating combined consumption around 4.9 liters per 100 kilometers. The engine’s compact architecture makes it particularly suitable for front-wheel-drive platforms like the forthcoming CLA, GLA, and A-Class models, where space optimization remains crucial.
NewsHaval H6 HEV : 243 hp hybrid SUV challenges Toyota RAV4 in 2026The modular design philosophy enables cost reduction through shared components while maintaining flexibility for different performance requirements. This engineering approach mirrors strategies seen across the industry, where manufacturers increasingly prioritize efficiency and production scalability over pure emotional driving characteristics. For enthusiasts seeking more visceral experiences, alternatives like the Ford Escort RS Mk1 by Boreham with its 330-hp naturally aspirated engine that revs to 10,000 rpm represent a completely different philosophy.
| Specification | M252 engine |
|---|---|
| Displacement | 1.5 liters |
| Configuration | Inline four-cylinder |
| Power outputs | 136 / 163 / 190 hp |
| Cycle type | Miller |
| Orientation | Transverse |
| Combined consumption | 4.9 L/100 km |
L’hybridation 48V comme réponse stratégique à l’électrification
Rather than committing fully to plug-in hybrid technology or pure electric powertrains, Mercedes implements a mild hybrid 48-volt architecture integrated seamlessly into the M252 powertrain. This system employs an integrated starter-generator connected to a compact lithium-ion battery, enabling more frequent engine stop-start cycles, discreet restarts, and supplementary electric torque at low speeds.
The 48V system recuperates energy during braking phases, extends coasting periods, and reduces consumption peaks in urban environments. While it cannot sustain prolonged electric-only driving, it enhances overall efficiency without imposing the complexity and weight penalties associated with full hybrid systems. This intermediate solution remains particularly relevant in markets where non-rechargeable powertrains maintain steady demand, especially within corporate fleets and among private buyers seeking balanced compromises between thermal and electrified technologies.
Key advantages of the 48V mild hybrid configuration include :
- Reduced mechanical stress on the starter motor through integrated starter-generator operation
- Smoother power delivery in stop-and-go traffic conditions
- Lower system complexity compared to high-voltage hybrid architectures
- Minimal impact on vehicle weight and packaging constraints
- Compatibility with existing thermal management systems
This approach contrasts with more aggressive electrification strategies, such as those adopted by manufacturers pursuing multi-purpose extreme 4×4 platforms combining traditional off-road capabilities with modern powertrains, which require substantially different engineering priorities.
Production chinoise et recentrage industriel européen
The most controversial aspect of the M252 project concerns its manufacturing location. This Mercedes engine is not assembled in Germany but produced in China through Horse, a joint venture co-owned by Geely, Renault, and other partners. Mercedes acts as a customer within this arrangement, purchasing completed engines for installation in European-market vehicles.
NewsBMW’s new off-road 4×4 to rival G-Class and Land Cruiser by 2028This decision reflects a broader strategic shift among European manufacturers : outsourcing certain thermal engines to Asian partners while retaining design, calibration, and software integration internally. The M252 case perfectly illustrates this trend—a vehicle conceived in Stuttgart, engineered according to German standards, yet equipped with a highly efficient thermal unit manufactured in China. High-performance AMG engines and six-cylinder blocks will remain German-made, but compact powertrains follow the logic of a globalized, rationalized marketplace.
This manufacturing strategy enables Mercedes to reduce production costs, ensure rapid scaling for thermal powertrains still present in model ranges, and maintain competitive pricing against rivals. The approach parallels developments in other sectors, including specialized performance applications like extreme rally-raid vehicles targeting championship victories with purpose-built drivetrains.
Perspectives d’usage et positionnement marché
Expected consumption figures place the M252 among the most frugal gasoline engines in the non-rechargeable category. The 48V system enables these values without fundamentally altering driver behavior, unlike plug-in hybrids requiring regular charging cycles. Paired with a dual-clutch automatic transmission, the M252 targets smooth urban efficiency rather than sporty character, with performance adequate for versatile usage but clearly oriented toward consumption reduction rather than emotional engagement.
This powertrain progressively replaces the M270 and M282 engines that previously equipped most Mercedes compact thermal models. This update responds to stricter European regulations and new expectations regarding CO₂ reduction. For owners concerned about maintaining comfort and reliability on their Mercedes vehicles through appropriate suspension upgrades, the M252-powered models will offer similar compatibility with aftermarket enhancements.
News$24,300, about the size of an MG ZS but better in every way — this SUV offers a stronger engine, superior handling, an ECO label, and 15.2 cubic feet of cargo spaceThe dual-transition strategy becomes evident : reducing fleet average emissions while maintaining competitive thermal offerings for markets not yet ready for complete electrification. In coming years, this powertrain type may well constitute the quintessential transitional offering—less complex than plug-in hybrids, more accessible than pure electrics, and sufficiently frugal to remain relevant within French and European regulatory contexts.
