Want autobahn-level V-8 power and emission-free electric propulsion in your performance sport sedan? This unlikely combination was more than enough to put the hybrid powertrain in the BMW M5 on our 2025 Wards 10 Best Engines & Propulsion Systems’ winners’ list.
In the seventh-generation M5, BMW puts under the hood an M-engineered turbocharged 4.4L V-8, hooked to an 8-speed automatic transmission that also houses the hybrid’s electric motor.
By itself, the V-8 produces 553 lb.-ft. (750 Nm) of torque from 1,800-5,400 rpm and 577 hp from 5,600-6,500 rpm, with a rev limit of 7,200 rpm, surprisingly high for a production V-8. The electric motor tacks on up to 194 hp and 207 lb.-ft. (281 Nm) of torque, punching total output to 717 hp and 738 lb.-ft. (1,001 Nm). Adding to the punch is a BMW-patented pre-gearing setup that boosts the small motor’s torque as high as 332 lb.-ft. (450 Nm).
The combination offers impressive response from launch to ludicrous speeds, in keeping with the M-brand heritage of bringing race-bred performance to the street. BMW says the all-wheel-drive M5 launches 0-60 mph (97 km/h) in 3.4 seconds while also jumping from 50-75 mph (80-121 km/h) in as little as 2.2 seconds, the latter a key part of our testing criteria. Employing Boost Control via a long tug on the lefthand shift paddle enables an extreme burst of thrust at 20-90 mph (32-145 km/h).
“While the BMW Neue Klasse next-gen electric platform and propulsion system is currently getting lots of attention, the BMW M5 sedan deserves plenty, too,” says 10 Best judge Gary Vasilash. “Yes, this is a plug-in hybrid, but the hybridization is all about power, something that a mere blip of the throttle tells you from the start.”
The EPA lists fuel economy at 50 MPGe using both the gas engine and electric motor and just a tick under 15 mpg (15.7 L/100 km) on gas only. Striving for the former is possible, primarily by keeping the 14.8-kWh lithium battery charged, either via the convenient front driver-side socket or through brake-energy recuperation. That regeneration can be enhanced by a setting that maximizes efficiency in the fifth-generation eDrive system. In our spirited driving, we averaged up to 27 mpg (8.7 L/100 km).
While the electric motor enhances high-end performance, the M5’s plug-in hybrid system adds quiet, emission-free driving whether around town or for electric-only operation up to 87 mph (140 km/h). BMW says the system can provide up to 25 miles (40 km) of pure electric driving, but in our testing the battery enabled up to 35 miles (56 km) of range.
The best part? Until you stop to plug it in, you’d never know you’re driving a hybrid thanks to the system’s seamless integration of engine and motor.
“The engine. The motors. The battery. The transmission. BMW crossed every ‘t’ and dotted every ‘i’ in thoroughly engineering each aspect of the M5’s plug-in hybrid powertrain to achieve performance greatness,” says judge Christie Schweinsberg, also appreciating that engineers didn’t skimp on fuel efficiency in their quest for enormous output.
“Despite frequently unleashing the M5’s massive horsepower and torque, I never got worse than 27 mpg,” she says. “For a vehicle that weighs 5,300 lbs. (2,404 kg) that is a remarkable achievement.”
