Mercedes-AMG is making a decisive move to re-embrace its performance heritage by phasing out the controversial four-cylinder plug-in hybrid powertrain, most notably seen in the AMG C63 S E Performance and GLC63 models. The shift comes in response to vocal customer feedback, which pointed to a disconnect between AMG’s traditional fan base and the high-tech but sonically uninspiring four-cylinder hybrid.
“Technically, the four-cylinder is one of the most advanced drivetrains available in a production car. It’s also right up there on performance,” a Mercedes source told Autocar. “But despite this, it failed to resonate with our traditional customers. We’ve recognized that.”
Back to the Classics: V-8s and Inline-Sixes Return
The move signals the beginning of the end for the M139 turbocharged 2.0-liter inline-four engine in AMG’s performance lineup. This powertrain, which debuted with 671 horsepower in plug-in hybrid applications, failed to deliver the visceral appeal and acoustic drama AMG customers expect, despite its engineering excellence.
Instead, Mercedes-AMG is doubling down on its traditional powertrains, with plans to reintroduce a new-generation V-8 and expand its use of the inline-six engine across models. Vehicles like the SL43 may soon ditch the four-cylinder in favor of the more robust inline-six, as AMG aligns with enthusiast demands.
The Two-Pillar Future: Combustion and Electrification
Michael Schiebe, head of AMG, confirmed at the reveal of the electric AMG GT XX concept that the company is adopting a “two-pillar” strategy for future models. This approach involves the coexistence of traditional combustion engines, including hybrids based on the V-,8 with a fully electric vehicle lineup built on the dedicated AMG.EA platform.
While Schiebe stopped short of confirming the official retirement date for the four-cylinder hybrid, he emphasized the importance of meeting customer expectations. “We need to cater to the demands of customers,” he said. “There are a lot of advantages of combining electric motors with combustion engines… so we want to offer different kinds of drivetrain opportunities.”
Why the Four-Cylinder Hybrid Missed the Mark
Despite the impressive horsepower and hybrid technology packed into the AMG C63 and GLC63, many critics and drivers felt the M139 engine simply didn’t deliver an emotionally engaging experience. Its “reedy” and “buzzy” sound was frequently compared unfavorably to the deep, thunderous roar of AMG’s iconic V-8s. In addition, the hybrid system added significant weight, nearly 5000 pounds, to the C63 without providing a substantial real-world performance improvement.
What’s Next for AMG?
Though no official timeline has been confirmed, reports suggest that the V-8 could return to the C63 as early as 2026. Until then, the four-cylinder hybrid will remain in production for select models. AMG’s long-term plan remains clear: continue pushing into electrification while preserving the soul-stirring performance DNA that built the brand.
In doing so, Mercedes-AMG hopes to bridge the past and future, offering cutting-edge electrified performance while rekindling the mechanical thrill that made it legendary.
