Sources have told Autocar that the new M5 will use the existing 4.4-litre twin-turbo V8, although improvements will see power rise to around 440kW.
At present the engine churns out 412kW/680Nm in standard trim, and 423kW/680Nm for the Competition Package models.
Perhaps most controversially, the M5 will abandon its rear-wheel drive heritage for a new rear-biased all-wheel drive system. Depending on the drive mode and situation, the car is capable of driving its rear wheels exclusively.
Improved traction will reportedly see the M5's 0-100km/h time drop from 4.3 seconds to around 3.5s.
If correct, these numbers will make the M5 more than competitive with the latest Mercedes-AMG E63, which in S guise has a 450kW/850Nm 4.0-litre twin-turbo V8, and a 0-100km/h time of 3.4 seconds.
The current M5's seven-speed dual-clutch transmission and the North America-only six-speed manual will be junked in favour of an eight-speed torque converter automatic by ZF.
The new M5 is said to weigh about the same as the outgoing model despite the larger body and the adoption of all-wheel drive. Part of this can be credited to the 5 Series' lighter, but stiffer, body structure, but the M5 will also feature a carbon-fibre roof and boot lid, as well as more aluminium components.
Back in August 2016, CAD/CAM renderings of the M5's more aggressively styled front and rear fascias were leaked online. In addition to this, the new M5 will feature wider front fenders with heat extraction vents.
It's said that the new M5 will make its debut at September's Frankfurt motor show. That means the new M5 won't filter through into Australian showrooms until 2018.