A FIVE-SPEED electronically controlled automatic is the only transmission on offer with the "businessman's M car", the 5 Series Sport. It allows the driver to choose between an adaptive shift program that monitors the driving style and external conditions such as terrain, or and a sports driving program. The Steptronic function also allows manual gear selection, with appropriate safeguards against faulty operation. All 5 Series Sport models are also fitted with diff ratios for quicker initial acceleration.