For the first time in its history, the iconic Mercedes G-Class in the U.S. will no longer feature a V-8 engine. Historically, every G-Class model sold in America, including the G500, G550, G55 AMG, and the twin-turbo AMG G63, has been powered by an eight-cylinder engine, with a few exceptions of limited-production V-12 variants. However, for 2025, Mercedes has replaced the G550’s 4.0-liter twin-turbo V-8 with a turbocharged 3.0-liter inline-six engine combined with a mild-hybrid system.
This new engine configuration, incorporating a 48-volt integrated starter-generator (ISG) between the engine and the nine-speed automatic transmission, delivers 443 horsepower and 413 lb-ft of torque. While this setup offers 27 more horsepower but 37 fewer lb-ft of torque compared to the V-8, the ISG provides an additional 20 horsepower and 148 lb-ft of torque at lower speeds, enhancing the vehicle’s initial responsiveness.
Despite these advancements, the absence of the V-8’s distinctive rumble is noticeable. Although the inline-six engine retains a degree of auditory presence, it often comes across as buzzy and less refined compared to the robust V-8, which is a remarkable departure from the G-Class’s traditional appeal.
Beyond the engine change, the 2025 G-Class maintains its classic exterior look with only minor updates such as a revised grille, new bumpers, and other subtle changes. The vehicle’s iconic design remains intact, preserving its retro charm. Inside, the cabin features minimal updates, including redesigned switchgear and the introduction of touch-capacitive steering wheel buttons, which have made some controls less user-friendly compared to previous models.
Performance-wise, the G-Class continues to excel off-road. During a test in southern France, the new model demonstrated impressive capability on challenging terrain, including steep, uneven rock faces. Despite the engine change, the G-Class remains a top performer in off-road situations, benefiting from features like the front locker that enhance its off-road prowess.
While the straight-six engine offers a more efficient and modern powertrain, the shift from the V-8 might affect enthusiasts who value the G-Class’s distinctive character. The G-Class remains a passion-driven vehicle, and despite the practicality of the new engine, many buyers may still prefer the traditional V-8 for its unique driving experience. Consequently, the sales split between the base G550 and the AMG G63, which is rumored to heavily favor the latter, might continue to reflect the enduring appeal of the V-8 engine.