Mercedes-AMG plants its 4.0-liter biturbo V-8 with flat-plane crankshaft into the 2027 GLE 63 S and GLS 63, delivering performance that breaks from the brand's recent electric pivot. Both SUVs gain the same powertrain architecture, creating a distinct split in Mercedes' lineup between electrified models and gas-powered performance variants.
The flat-plane crank V-8 represents AMG's commitment to internal combustion at the high end. This architecture reduces reciprocating mass compared to traditional cross-plane designs, enabling higher rev limits and sharper throttle response. Mercedes packages this engine in two of its largest SUVs, signaling that gas power remains viable for luxury performance buyers who reject fully electric drivetrains.
The GLE 63 S targets the sport-luxury coupe SUV segment, while the GLS 63 addresses buyers wanting three-row capability with serious power. Both vehicles sit atop Mercedes' SUV hierarchy, priced well above entry models and competing directly with BMW's X5 M and X7 M variants, as well as Porsche's Cayenne Turbo offerings.
This move reflects fragmented market demand. While Mercedes accelerates EV development elsewhere in its range, high-net-worth customers for AMG models show persistent preference for V-8 engines. The 2027 models arrive as competitors increasingly downsize to six-cylinder turbos or switch entirely to electric power, making these big V-8 SUVs rare creatures in an industry trending toward efficiency.
The flat-plane crank V-8 already serves the AMG C 63 and E 63 sedans, establishing AMG's confidence in the platform's reliability and performance metrics. Extending it to GLE and GLS models grants these large