What it is:
Select Shift Manual (SSM) and Auto Shift Manual (ASM) use a combination of Auto-Clutch and Shift-By-Wire electronic control system technology to provide the customer a fun-to-shift experience along with significant fuel economy improvements over a base manual transmission. The Select Shift Manual mode allows a customer to command gear changes according to his/her personal preference like a conventional manual transmission. The Auto Shift Manual mode provides the customer automatic gear shifting much like an automatic transmission.

How they work:
Both the Auto-Clutch subsystem and Shift-By-Wire subsystem use an electro-hydraulic or electro-mechanical actuation system controlled by a stand-alone transmission control module. A customer requests a gear shift by using the appropriate driver interface mechanism (shift lever, push buttons, etc.)

In place of the usual cable/linkage (which is eliminated), a sensor informs the controller of the requested gear shift. The controller processes the request and commands the actuators to open/close the clutch and disengage/engage the gear sequence with very fast response times. Engine torque is controlled during the shift either by controlling the throttle directly (Drive-By-Wire) or enabling ignition/fuel injection control to provide smooth shifts.

Customer benefit:

Fuel economy improvement with fun-to-shift convenience and shift mode flexibility.