2020 MERCEDES-BENZ S-Class M256 (3.0L inline-6 mild hybrid)/M177 (4.0L twin-turbo V8 petrol) (W223)
W223 / Sedan / Global (including Europe, North America, China, and other major markets)
M256 (3.0L inline-6 mild hybrid)M177 (4.0L twin-turbo V8 petrol)OM656 (3.0L inline-6 diesel, selected markets)OM656 (2.9L inline-6 diesel, selected markets)M264 (1.5L inline-4 mild hybrid, selected markets for S 450)M173 (4.0L V8 biturbo hybrid in AMG S 63 variant)Exakter Jahres-/Varianten-DatensatzGold
Engine identity
Oils and fluids
Service and parts data
Common and chronic problems
- Early W223 models reported minor electrical and software bugs, typically addressed via software updates.
- High complexity of hybrid system requires specialized service.
First checks
- Verify software for latest updates via authorized Mercedes-Benz service.
- Inspect mild hybrid system battery and belt-driven starter-generator condition.
- Check for any recalls or service campaigns related to driver assistance systems.
Vor dem Teiletausch
- Save fault codes and freeze-frame data before clearing anything.
- Check engine oil, coolant and transmission fluid using the correct temperature and service procedure.
- Verify power, ground, connectors, hoses, leaks and live data before replacing expensive parts.
Important notes
- Engine and feature availability subject to market-specific emissions regulations and model year changes.
- Diesel engines mainly for Europe, Middle East, and select international markets.
- Mild hybrid technology (EQ Boost) introduced in inline-6 petrol engines globally.