Which lock-up component is usually located in the front half of the converter shell?

Which lock-up component is usually located in the front half of the converter shell?

• A. Backing plate
• B. Friction disc
• C. Ground shaft
• D. Hydraulic piston

Answer: (D)

In a torque converter, the lock-up clutch is engaged by hydraulic pressure acting on a piston. This piston clamps the lock-up friction discs together, creating a direct drive and reducing slip at cruising speeds. Because the lock-up mechanism needs ready access to hydraulic fluid, the piston is placed in the front portion of the converter shell where fluid pressure can be applied efficiently and routed easily from the transmission pump. The backing plate mainly provides support for the clutch pack and seals, not the actuation. The friction disc is part of the clutch pack itself, not the component that creates the actuation. The ground shaft isn’t a lock-up component at all. Therefore, the hydraulic piston is the best answer.

In a torque converter, the lock-up clutch is engaged by hydraulic pressure acting on a piston. This piston clamps the lock-up friction discs together, creating a direct drive and reducing slip at cruising speeds. Because the lock-up mechanism needs ready access to hydraulic fluid, the piston is placed in the front portion of the converter shell where fluid pressure can be applied efficiently and routed easily from the transmission pump.

The backing plate mainly provides support for the clutch pack and seals, not the actuation. The friction disc is part of the clutch pack itself, not the component that creates the actuation. The ground shaft isn’t a lock-up component at all. Therefore, the hydraulic piston is the best answer.