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Sequential Manual Transmission
From Wikipedia, the free encyclopedia
Toyota's SMT or Sequential Manual Transmission, is currently offered in the 3rd generation Toyota MR2
It is probably the most affordable electrohydraulic manual transmission offered in any sports car. In comparison the Ferrari's F1 system would cost approx. $10,000.
Unlike a Tiptronic, Toyota's Sequential Manual Transmission/SMT is a computer controlled clutch mechanism on a manual transmission using hydraulic actuators, or electrohydraulic manual transmission. When the driver enters the car, hydraulic actuator pressurising can be heard. The car behaves just like shifting gears with a common manual gearbox while the clutch and the throttle work is computer controlled. It features some smart logics to help the driver. It automatically shifts down to 1st gear when the car slows down to stop. The car engages into neutral when brake is not applied for more than 90 seconds. Warning beeps can be heard when the gear you are in is too high for the speed. The car will not start unless brake is applied while in neutral. You should be in a gear to avoid the car rolling when parked, just like a manual car. The car is much fun and easy to drive with a little chance of making a mistake.
The downshifts are amazingly quick and precise, and it replicates a heel-toe downshift performed by a professional driver.
However, its upshifts are not as quick as the more expensive transmissions made by BMW and Ferrari. While the transmission shifts fairly quickly at lower RPMs and under gradual acceleration, there is noticeable hesitation when shifting close to the redline at wide open throttle. This significantly affects the car's maximum acceleration. Conventional manual MR2s can reach 0-100km/h in 7-7.5 seconds. The SMT versions can only do it in 8-8.5 seconds. Drivers are advised to slightly let up on the gas pedal before shifting.
Many owners of the MR2 SMT have been hoping for Toyota or its tuning wing TRD to deal with this issue through aftermarket support. It is certain that the SMT, and the MR2 would be much more popular among enthusiasts if it was more performance oriented. Currently, many people who would like an SMT initially, chose to settle with a conventional manual transmission due to performance reasons. Having been introduced in 2002 MR2 Spyder, SMT underwent updates in later model years (such as switching from a 5spd to a 6spd and updated firmware that improved shifting performance).