Update - BMW have released new details of the upcoming M5. You can read our coverage here
The new BMW M5 has been spied testing on the Nurburgring, revealing more about how the production car will look.
The latest M5 prototype has lost some of the false body panels used on earlier evaluation vehicles. We can now see the shape of the M5's lower air intakes and their honeycomb inserts, as well as the signature M division wing mirrors.
Around the back, the rear diffuser-style element is now visible, although the lower rear reflectors should be ignored, as they're temporary units.
This car is also using undisguised versions of the head- and tail-lights seen elsewhere on the 5 Series sedan range.
The next-generation sports sedan will reportedly feature an updated 4.4-litre twin-turbo V8 generating over 447kW (600hp). Standard all-wheel drive will help the car complete the 0-100km/h standard in under 3.6 seconds.
That's quicker than today's Competition Edition model, which has a 423kW/680Nm version of the twin-turbo V8 motor, and is capable of a 0-100km/h time of 4.2 seconds.
Thanks to the use of lightweight materials, including aluminium components and a carbon-fibre roof, the new M5 will weigh around the same as today's model despite featuring a larger body and standard all-wheel drive.
A report in March also claimed the new M5 would ditch its current seven-speed dual-clutch transmission and the North America-only six-speed manual in favour of a ZF-sourced eight-speed torque converter automatic.
Rumours indicate the next-generation M5 will be revealed at or just before the Frankfurt motor show in September. If so, it seems unlikely the new M5 will go on sale down under before 2018.