When the F90-generation BMW M5 was officially debuted, the idea that it had xDrive all-wheel drive was shocking to most enthusiasts. Well, we actually knew it was happening for some time but, still, seeing an all-wheel drive M5 was a bit odd. The BMW M5 has a long history of being rear-drive, so this new F90’s xDrive all-wheel drive system is quite a big step for the M5. However, it wasn’t always going to be that way. According to Autocar, the very first prototype of the F90 M5 was actually rear-wheel drive.
Sticking with tradition and the car’s roots, BMW’s M Division likely didn’t even think twice about making the F90 BMW M5 rear-wheel drive. Until they drove it, that is, and realized that it had far too much power and performance for just two driven wheels. “It was the natural, historic way to go – until we realized we were beyond the limits of longitudinal acceleration. Four-wheel drive was the only option.” BMW M Vice President Dirk Hacker told Autocar.
And Hacker’s obviously right. The new F90 BMW M5 packs 600 hp and 553 lb-ft of torque from its twin-turbocharged 4.4 liter V8. That’s simply too much power for just the rear wheels. Now, if you’re thinking that it’s not too much power for just to tires to handle, as the F10 BMW M5 30 Jahre made 600 hp as well as was rear-wheel drive, that car wasn’t anywhere near as fast as it could have been had it driven all four wheels. Also, it really enjoyed turning rubber into smoke.
This new BMW M5 is all-wheel drive so it can put all 600 horses and all 553 lb-ft of twist to the road with minimal slip. That means it’s good for 0-60 mph in 3.2 seconds, which makes it the fastest accelerating production BMW of all time. So, clearly, giving it all-wheel drive was the right move. But BMW M didn’t just stop there. This new M-specific xDrive all-wheel drive system can effectively shut off its front driveshaft and axles, turning it into a pure rear-drive M5 for as long as the driver wants it to be. That makes the BMW M5 the best of both worlds: an all-wheel drive super sedan/rocket ship and a rear-wheel drive hooligan. Only the press of a button separates the two.[Source: Autocar]