BMW’s SMG (Sequential M Gearbox) was first seen on U.S. shores in the high performance E46 M3. The SMG transmission is shifted with paddle shifters similar to a Formula One car in the manual setting or like a conventional automatic when the transmission is placed in auto mode. Owners unfamiliar with SMG may find it slightly jerky when they first drive it, but with familiarity and practice, using this gearbox becomes an easy, satisfying process.
Drive smoothly. Like any other gearbox, whether it’s an automatic or a manual, the SMG transmission responds well to smooth throttle and braking inputs. This is true if SMG is in manual mode where the driver is shifting or simply left in auto mode where the gearbox itself is responsible for shifting.
Feather the throttle when upshifting. SMG can be shifted up through the gears without lifting off of the throttle but, much like a conventional manual transmission, it responds more smoothly when the driver lifts her foot off of the accelerator a little right before her hand shifts to the next gear with the steering wheel mounted paddles. This will help the gearbox shift up through the gears more smoothly and give it time to engage the clutch, select the next gear and then release the clutch, which is the chain of events that the paddle begins.
Downshift when you are braking to a stop or slowing for a corner. As speeds decrease, select the next lower gear, but do not shift so soon that the engine’s rpms are brought up to high or suddenly. Ideally, you should downshift to place the engine in the middle of the power band, around 3,000 or 4,000rpm. While you can let the gearbox handle the downshifts automatically, downshifting the transmission yourself will keep you more in tune with what the car is doing.
Downshift in a straight line when slowing for a corner. Try to avoid shifting the SMG gearbox in the middle of a corner, especially if you are driving in a spirited manner. Shifting when cornering has more of an effect on your BMW’s stability than it does in a straight line, so concentrate on slowing and downshifting and then turning in for the corner.
Use sport mode. SMG has a normal mode and a sport mode. Sport mode shifts the gearbox through the gears more quickly and may lead to a smoother driving experience. The normal mode shifts slower, which may make it more difficult to drive smoothly and seamlessly. Drive the car frequently. An SMG gearbox takes time and experience to become familiar with its behaviour.