A preselector gearbox allows the driver to select the next gear ratio using a small lever on the steering column or dashboard without immediately changing gears. When the driver is ready, pressing and releasing a dedicated pedal engages the pre-chosen gear. This design was widely used in early luxury cars and racing vehicles before fully automatic transmissions became standard, as it eliminated the need to double-clutch or rev-match.
I need to rebuild the preselector on this old Riley, because third gear won't engage when I drop the pedal.
Driving a preselector requires a completely different rhythm than a standard manual, as your hands and feet are working out of sync on purpose.
Also heard as
- preselector gearbox
Related terms
Manual transmission
A gearbox requiring the driver to manually select gear ratios using a shift lever and a clutch.
Clutchless manual transmission
A gearbox that requires manual gear selection but automates the clutch operation.
Double-declutch
A manual shifting technique where the clutch is engaged in neutral between gears to match transmission speeds.