Spies lift lid on 2010 6 Series

The current 6 Series, facelift in 2007, has been a roaring success for BMW with more than 20,000 units sold each year. UK sales were mostly dominated by the diesel range which accounted for 65% overall sales.

BMW was at one point toying with seven different concepts: a four-seater coupé and cabriolet, a coupé-cabrio with retractable hard top, a slightly more compact two-seater Mercedes SL rival, a pillarless four-door coupé with rear suicide doors, a four-door four-seater Z6 coupé like the CS show car, and a three-door shooting brake.

To fix the slightly odd proportions, BMW designers will shorten the overhangs and extend the wheelbase by 80mm. Munich's designers will also shorten the nose by 40mm – no mean feat in view of the more stringent pedestrian protection regulations now throttling car stylists. The roofline will be lowered slightly, and the overall effect will – on the finished production car – produce a sportier and more aggressive stance. Although this will be a subtle upgrade, the 6-series v2.0 will have a few design flourishes of note. Expect new split taillights, fresh wraparound headlamp and indicator units, an even wider kidney and the characteristic belt crease which drops from bonnet to rear bumper level. The biggest detail improvement over the current car is the absence of ungainly B-posts, insiders claim. As a result, even the 6-series coupé boasts four fully retractable side windows.

The vehicle spotted testing in Germany has a cloth soft top, but closer examination suggests that this may also be part of the camouflage. The wrapped decklid gives the impression that this is a convertible, so the next 6 Series just might sport a retractable hardtop, to compete with Mercedes’ SL.

Prices for the new model will soar. Today a 650i soft-top currently undercuts the SL500 by £15,000 – but that gap will narrow. To justify the extra dough, the new 6 Series will come with a more generous standard equipment along with an uprated interior. Out goes the unloved SMG gearbox, replaced by a new Getrag-developed seven-speed dual-clutch paddleshift transmission.

Under the hood, a turbocharged, 306bhp straight six, new twin-turbo 408bhp V8 and the 507bhp V10 implanted into the M6 will be offered. Diesel engine may stay the same but are very likely to be tweaked to offer lower CO2 emissions, more power and fuel economy. Thanks to the new twin-clutch gearbox, there will no longer be a manual option. Mercedes is readying 4WD versions of the new E-class Coupe and next-gen CL, so BMW could follow suit.

The newcomer is likely to get very luxurious amenities like heated head restraints, a power-operated wind deflector, active cruise control with brake-to-stop mode, VDC (variable damping control, which also includes adjustable springs), DPC (dynamic performance control, active rear differential) and TLC (tactile lane control via intermittent vibrations in the steering wheel).

The convertible will be launched in 2011 while six months down the line, the coupe will also launch. Expect an "M6" variant sometime in 2012.