The Mercedes-Benz S-Class has been fully redesigned for 2021. In addition to fresh styling both inside and out, the new S-Class offers updated in-car tech, an even more advanced suite of driver aids and a pair of new engines, with more powertrains to follow. This is all to help it better compete against rivals that include the Audi A8 and BMW 7 Series, both of which have undergone full redesigns since the outgoing S-Class debuted in 2014. Not that the S-Class needed much improving, as it has continually been one of Edmunds' top-rated sedans.
While the S-Class has always been a comfortable, well-appointed and tech-forward vehicle, it's never been known as a driver's car, save for the rarefied AMG models. The story has changed with the new one, at least according to Mercedes. Not only does the S 580 4Matic's twin-turbo V8 make more power than before, but Mercedes' engineers have tuned the adaptive air suspension to improve handling.
Do these distinctions make a difference? There was only one way to find out. We took a 2021 Mercedes-Benz S 580 4Matic to the Edmunds track for our full battery of tests, and here's what we found.
How did the S 580 4Matic perform?
Like last year's S 560 4Matic, the 2021 S 580 4Matic uses a 4.0-liter twin-turbocharged V8 engine. Output is up by 33 horsepower for a total of 496 hp, though torque remains the same at 516 lb-ft. For 2021, Mercedes has also fitted the V8 with its EQ Boost mild hybrid system. In addition to smoothing out shifts from the nine-speed automatic and improving fuel economy, the system helps improve acceleration by filling in low-end power before the turbochargers really get going.
As expected, the 2021 S 580 4Matic is quicker than the outgoing S 560, though not significantly so. It hit 60 mph in 4.7 seconds, shaving just 0.2 second off the last car's dash to 60 mph, while its speed at the quarter-mile mark ("trap speed") also improved only modestly at 110.8 mph versus 108.2 mph.
Looking at segment rivals, the S 580 4Matic edges out the entry-level Porsche Panamera to 60 mph and widens the gap considerably by the quarter mile. You can go much faster in fancier Panameras, but it'll cost you. A direct rival to the S 580 is the BMW 750i xDrive, which handily beats the Benz's acceleration times and trap speed. The S 580 trails the pack in braking distance by a wide margin, which we're hoping is mostly due to our test car's all-season tires as opposed to the grippier summer performance tires worn by the BMW and Porsche.