Electrohydraulic manual transmission

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Electrohydraulic manual transmission or clutchless manual gear system is a manual transmission system that works similar to a manual transmission but operates the clutch automatically. To change gears, the driver selects the desired gear, and the system automatically operates the clutch and throttle to match revs and engage the clutch again. Depending on the implementation, some transmissions will automatically shift gears at the right points and others require the driver to manually select the gear even when the engine is at the redline. Also, many such transmissions operate in sequential mode where the driver can only upshift or downshift by one gear at a time. Despite superficial similarity, clutchless manual transmission differ significantly in internal operation and driver's 'feel' from manumatics, which are automatic transmissions (using torque converter instead of clutch to manage the link between the transmission and the wheels) with ability to signal shifts manually.

BMW's version of this system is called SMG, for sequential manual gearbox; it is used in the M3, among other models. The BMW SMG transmission has both automatic and manual shift modes. Inside the different modes there are different programs, with six settings to control the upshift/downshift speed for manual operation, and five settings for automatic mode. Toyota also had a similar transmission on the MR2 Spyder, which is known as the Sequential Manual Transmission, or just SMT'. Alfa Romeo introduced electrohydraulic manual transmission Selespeed in Alfa Romeo 156 in 1999.