The German automaker is preparing to manufacture a new 4-door coupe - spies managed to steal sketches news from the patent office. The new model will be built on the platform 6 Series. The basis for the Germans put the BMW concept Gran Coupe, introduced last year. So far, no information, what name will get this coupe. The auto experts have a few guesses on this - 6-Series Gran Coupe or 6-Series Gran Turismo. The production of this coupe should start as early as next year. So customers can expect to receive the car by the end of 2012. And presentation of the new product will most likely take place this fall at the motor show in Frankfurt. 4-door coupe from BMW will be a worthy rival Mercedes-Benz CLS and Audi A7 Sportback. Specifications 4-door coupe BMW kept secret. It is possible that the novelty will receive the same motors as the "donor" - BMW 6-Series. Recently spies spotted the new BMW 3-Series.