Mercedes-Benz is preparing a significant refresh of its flagship S-Class sedan. While marketed as a facelift, the changes run deep, with around 2,700 parts redesigned or re-engineered. The most notable update is a new version of the 4.0-liter twin-turbo V8 engine—the M177 Evo—which now features a flat-plane crankshaft instead of the conventional cross-plane design.
Why This Matters: The Shift to Flat-Plane Cranks
The move to a flat-plane crankshaft is not just about performance. Flat-plane designs are known for quicker throttle response, smoother operation, and reduced vibrations. Traditionally found in high-performance sports cars, they are now migrating into luxury vehicles like the S-Class. This is driven by two key trends: the demand for more responsive engines and increasingly strict emissions regulations. A flat-plane crank can contribute to better combustion efficiency, helping automakers meet those standards.
Engine Performance and Expansion
The M177 Evo will debut in the 2027 S580 mild-hybrid, where it will produce 530 horsepower—a substantial increase from the current model’s 496 hp. Mercedes-AMG has confirmed that this engine will also power other vehicles, including the updated S63 and potentially the new CLE 63. This suggests a broader strategy to elevate performance across the luxury lineup.
Interior and Exterior Updates
The exterior design will remain largely unchanged, but the headlights and taillights will feature new star-pattern LED signatures. The interior is undergoing a more dramatic overhaul, shifting away from the current S-Class’s distinctive four-vent dashboard and floating infotainment screen. Instead, it will adopt a design closer to the all-electric EQS, which some observers question as a downgrade.
The shift to flat-plane crankshafts in luxury vehicles is a sign that automakers are prioritizing not just power but also refinement and efficiency.
The 2027 Mercedes-Benz S-Class facelift represents a substantial evolution under the skin. The new V8 engine, combined with design updates, positions the S-Class to remain at the forefront of luxury performance. Whether the interior changes will resonate with buyers remains to be seen, but the mechanical improvements are clear.
