Dual clutch transmissions (DCTs) combine the efficiency of manual transmissions with the convenience of automatics.Checked 2026-08-12
Dual-clutch transmission (DCT)
An automatic built from two gearsets, each with its own clutch, so the next gear is pre-selected.
Also called: DCT · DSG · PowerShift · S tronic · dual clutch
What it means
Definition
A dual-clutch transmission is effectively two gearboxes in one housing — one clutch handling odd gears, the other even — with a computer opening and closing them in place of a torque converter. That lets the next gear engage while the current one is still driving. The clutch packs are either dry or bathed in fluid; LuK, an OE clutch maker, notes that the dry clutch has only limited thermal capacity, so that under large energy inputs the system quickly reaches its limits, which are significantly below those of comparable automatic torque converters or wet clutches.
Why a buyer cares
What it changes
Dry and wet versions are different machines to diagnose and service, and a listing rarely says which one a car has — the transmission's name usually has to be looked up.
In practice
Where you meet it
In spec lines as DCT, DSG, PowerShift or S tronic, and on estimates naming a clutch actuator or mechatronic unit rather than a torque converter.
Two things that look alike
Not the same as
A conventional automatic uses a torque converter; a CVT uses pulleys and no fixed gears at all.
Read next
Related terms
Continuously variable transmission (CVT)
An automatic that uses variable-diameter pulleys instead of a fixed set of gears.
Dual-mass flywheel (DMF)
A two-part flywheel with springs between the halves, used on many manual cars to damp engine pulses.
Valve body and shift solenoids
The hydraulic control block inside an automatic, and the electrical valves that operate it.
Where it shows up
Related problem files
Where this comes from
Sources
The dry clutch has only limited thermal capacity, so that under large energy inputs the system quickly reaches its limits, which are significantly below those of comparable automatic torque converters or wet clutches.Checked 2026-08-12