Spy shot BMW 5-Series

It is about to pick up the lower-and-longer lines of the upcoming BMW GT Concept, which are also reflected in the latest Z4 coupe-convertible.

The 5 Series is well into testing in Europe as BMW's new-model rollout plan has it following the 7 Series flagship, which was previewed last year and goes on sale soon in Australia.

The new 5 is called a 2010 model, which means sales in the final quarter of this year in the USA and a likely preview appearance at the Frankfurt Motor Show in October.

It was caught during testing in Germany and, despite heavy camouflage cladding, the new shape is obvious and a contrast to the current Five.

It is expected to come with more conventional headlamps, a more prominent version of BMW's signature 'twin-kidney' grille and a cleaner front end.

The new 5 Series is known inside BMW as the 'F10' and is a major change.

Apart from a shorter front overhang, it has a wheelbase which has been stretched by nearly 10 centimetres to improve cabin space and a wider track. But the overall length is only increased by two centimetres and the height is being reduced slightly.

It will roll on standard 17-inch alloy wheels with optional wheels in 18 and 19-inch sizes.

Mechanically, the basic engine is expected to be a 2.5-litre six with the current 4.8-litre V8 at the top end.

But European sources say that, despite BMW's switch to turbocharged engines for its performance cars, that a more-powerful version of the 5-litre V10 used in the current M5 is also in the works for the new model.