2025 BMW M5 Sedan Review: The Heavy Toll of Hybridization

The 2025 BMW M5 Sedan, known internally as the G90, marks a significant departure from its predecessors by introducing a plug-in hybrid drivetrain to the flagship performance model. It positions itself in the high-performance executive saloon segment, competing primarily with heavily electrified models from other German premium brands. The larger dimensions of the saloon mean it now measures over five meters in length, expanding its presence on the road. In Germany, the saloon carries a base price of 144,000 euros, while its immediate rivals include the Mercedes-AMG E 53 Hybrid 4Matic+ at 109,242 euros, the Porsche Panamera 4 E-Hybrid at 123,400 euros, and the Porsche Panamera Turbo E-Hybrid at 198,000 euros.

The high-voltage battery under the floor of the saloon provides energy to the electric motor. For those daily commutes where silent travel is preferred, the system can operate solely on electricity at speeds up to 140 kilometers per hour. WLTP figures suggest that the sedan achieves a combined fuel consumption of 1.6 to 1.7 liters per 100 kilometers when starting with a fully charged pack. Cautious driving under ideal conditions should yield a reasonable amount of electric driving, though these official ratings represent an idealized laboratory test. For the German market, the manufacturer claims an electric range of 67 to 69 kilometers on a single charge of its high-voltage battery.

Real-world electric range typically falls short of laboratory figures depending on driving style, ambient temperature, and highway speed. Real-world testing in Europe suggests that drivers should expect a reduction of 15 to 30 percent compared to the official range. On the autobahn at a steady 130 kilometers per hour in mild weather, the usable electric range is estimated to fall to approximately 45 kilometers. In urban environments with frequent deceleration and energy recovery, an estimated city range of 55 kilometers is achievable. When the battery is completely depleted, the vehicle relies entirely on the 4.4-liter combustion engine, which draws from a 60-liter fuel tank.

The M5 uses a lithium-ion pack with nickel-manganese-cobalt chemistry, with a net usable capacity of 18.6 kilowatt-hours. This specific chemistry provides high energy density and the rapid discharge needed to support the electric motor during hard acceleration. However, nickel-manganese-cobalt cells are more sensitive to temperature extremes than lithium-iron-phosphate alternatives, meaning the thermal management system must work harder during winter cold and summer heat. Over several years of ownership, frequent rapid discharging and charging cycles will contribute to gradual degradation of the pack capacity, although the chemistry is well-proven in performance applications. Charging is limited to 7.4 kilowatts of alternating current, meaning a full charge takes approximately three hours and fifteen minutes.

BMW built this seventh-generation model on its Cluster Architecture platform, which also supports conventional internal combustion and battery-electric vehicles. This shared platform approach means the M5 must accommodate both a heavy twin-turbocharged V8 engine up front and high-voltage battery components under the passenger cell. The body construction utilizes high-strength steel and aluminum, but the sheer volume of mechanical parts results in an unladen weight of 2,435 kilograms. To mitigate this mass during acceleration, the electric motor uses a pre-gearing stage that increases its nominal torque of 280 Newton-meters to an effective 450 Newton-meters at the transmission input. The thermal management system is busy, featuring separate cooling loops for the hot engine block, the coolers, and the high-voltage battery pack. The electric motor is integrated directly into the housing of the eight-speed automatic transmission.

The combined torque of the hybrid powertrain reaches 1,000 Newton-meters.

The chassis relies on a double-wishbone front suspension and a five-link rear setup, using standard steel springs and adaptive dampers. This hardware must control a significant amount of weight, which usually dulls the agility of a performance saloon. The way the dampers manage the 2.4-tonne curb weight in tight corners is somewhat like watching a heavy commercial printing press operate at high speed; there is a massive amount of moving metal, but the precision is undeniable. BMW has tuned the active suspension to mask the mass as much as physics allows, providing good body control during fast direction changes. The steel springs provide a firm ride at lower speeds, although the dampers soften sufficiently on the highway to deliver long-distance comfort. Active rear-wheel steering is included as standard, tilting the rear wheels up to 1.5 degrees to assist in tight maneuvers.

Inside, the dashboard is dominated by BMW’s curved display housing a 12.3-inch instrument cluster and a 14.9-inch touchscreen. The cabin materials are assembled with the neatness expected of a luxury brand, featuring carbon fiber accents and leather surfaces. However, the driver interface relies heavily on the screen, which handles everything from navigation to the basic functions of the climate control. Adjusting the air conditioning or activating the seat heating requires tapping through multiple menus on the screen, a task that cannot be performed safely without diverting attention from the road. The lack of tactile controls for these common adjustments remains a significant distraction during daily driving. Physical buttons for the seat heating, fan speed, and temperature are absent, requiring the driver to tap through several layers of the software.

Passengers in the back seat will find a wheelbase of over three meters, which provides adequate legroom for adults. The standard Bowers and Wilkins surround sound system provides excellent audio clarity, and the suite of driver assistance systems operates smoothly on the autobahn. My son, who monitors these things from his smartphone, informs me that the M5 has become a meme for its weight, though he has never had to park one. He was, however, more interested in the digital light show within the illuminated grille than the hybrid architecture beneath it. In hindsight, these design details and the hybrid configuration are clearly intended to broaden the appeal of the model in global markets where straight-line acceleration and digital features are popular. The luggage compartment offers 466 liters of cargo space, which is 64 liters fewer than the non-hybrid 5 Series sedan due to the packaging of the power electronics.

The combination of a twin-turbocharged V8 engine, an electric motor, and a high-voltage battery system represents a complex mechanical layout. The brand’s reputation for reliability in its standard passenger cars is solid, with favorable ratings in German breakdown statistics. However, high-performance M models operate under greater thermal and mechanical stress, which demands regular maintenance. For this new G90 generation, an early recall was already issued regarding a potentially faulty double-cardan joint in the steering column that could affect steering control. Given the complexity of the cooling systems and the dual-propulsion system, long-term ownership costs are likely to be substantial once the manufacturer warranty expires. Owner reports from the previous generation suggest that the twin-turbo V8 requires careful maintenance of its cooling hoses and oil lines.