What's Inside A Converter?
A torque converter is a pump. It shares fluid with the transmission.
Inside the big donut-shaped torque converter housing is an impeller, which is driven by the engine. The impeller's fins (or vanes) create centrifugal force by pumping transmission fluid outward i.e., toward the outside of the torque converter.
Bob Ritzman of B&M Racing likens the car's motor to an electric fan and the torque converter to a pinwheel. When you turn the fan on, if it's facing the pinwheel, the pinwheel will spin because of the air that's flowing across it. You have to look at the pinwheel as being the turbine, or the output member of the torque converter. That piece is attached to the input shaft of the transmission.
The other key component inside the torque converter is the stator, which we've mentioned. Its located between the impeller (on the input side) and the turbine (on the output side). The stator incorporates a one-way clutch, which has the ability to redirect the fluid flow inside the converter.
As the oil flows through the converter and comes out of the turbine, says Ritzman, it goes through the stator, which redirects the oil flow. And by redirecting the oil flow, that's where you achieve the torque multiplication.