A New Era Hybrid Super Sedans: Here's Why The 2025 BMW M5 Weighs More Than A Full-Size Pickup

What’s behind the 2025 BMW M5’s weight-gain

Let’s get real about this weight issue. BMW’s decision to ditch pure ICE technology in favor of a plug-in hybrid powertrain is the main culprit behind the new M5’s extra pounds. This new setup features an identical powertrain to the standalone BMW M car, the XM, that packs a new 4.4-liter twin-turbo V8 (codenamed S68) with an e-motor stuffed into the gearbox. Together, the hybrid powertrain pushes out an astonishing 717 horsepower and 738 pound-feet of torque. Impressive, right? But it comes at a cost.

The e-motor is powered by a 14.8 kWh battery pack, which is good for about 25 miles of E.V.-only range but adds a significant chunk of weight, estimated to be around 400-500 pounds. Then there’s the electric motor, the wiring, and all the other bits and bobs that make the hybrid system work. It all adds up, and before you know it, you’ve got a super sedan that’s tipping the scales at a whopping 5,390 pounds! The good thing is that BMW didn’t downsize the combustion engine like how Mercedes did with the AMG C63 S E Performance. To give some context of just how heavy BMW’s sports sedan is, here’s a look at some of the vehicles in the luxury class, which weigh less than the 2025 M5.

Now, to be fair to BMW, it hasn’t completely ignored the weight issue. Despite being well-kitted out, the Bavarian automaker used lightweight materials like a carbon fiber roof and some body panels, including the rear diffuser. The optional carbon ceramic brakes are said to save 55 pounds compared to the standard steel rotors. But it’s clear that those efforts haven’t been enough to offset the heft of the hybrid system.

So, can 717 horsepower really make up for all that extra weight? Well, in a straight line, absolutely. The 2025 M5 is still a rocket ship, capable of hitting 60 mph in 3.5 seconds, which isn’t slow by any means. However, the new-gen M5 is two-tenths of a second slower to 60 than the model it replaces, which is expected since its power-to-weight ratio has worsened compared to the outgoing M5. BMW has always understated its vehicles’ performance, and we think the new M5 should be quicker to 60 mph than the official claims.

Additionally, the increment in curb weight could affect the M5’s handling. It could feel less nimble and planted than its predecessors, and it might not be as eager to change direction on a twisty back road.

The Porsche Panamera Turbo E-Hybrid sets the bar high for performance hybrid supersedans

In the high-performance plug-in hybrid sedan world, the new M5 isn’t the only option available. Porsche offers the Panamera Turbo E-Hybrid, which is currently the most potent Panamera model to exist.

The Panamera Turbo E-Hybrid, while not featherweight at 5,302 pounds, undercuts the M5’s 5,390-pound curb weight. Power-wise, its 4.0-liter V8 and an e-motor produce a combined 670 horsepower and 686 pound-feet of torque; down on both horsepower and torque numbers compared to the 2025 M5. However, you should note that the new Panamera Turbo E-Hybrid boasts a larger 21.8 kWh battery pack, which is estimated to give the sedan an E.V.-only range of 30 miles, which is five more miles than the BMW. It’s fascinating how Porsche managed to keep the Panamera Turbo E-Hybrid’s weight in check, even with a larger battery pack as opposed to the latest M5.

So, does the reduced weight of the Panamera Turbo E-Hybrid give it an advantage over the M5 when it comes to the power-to-weight ratio? Well, that may not necessarily be the case. While the 2025 BMW M5 weighs more and produces more power than the Porsche, the Panamera Turbo E-Hybrid’s slightly lower weight means it should be able to corner better than the chunkier M5. In the end, we won’t really know how the two fare against each other, until we can have a proper track battle and determine which is quicker. Watch this space.