Torque Converter
DESCRIPTION
| 1 - Turbine | 4 - Input Shaft |
| 2 - Impeller | 5 - Stator Shaft |
| 3 - Stator | 6 - Turbine Damper |
The torque converter must be replaced if a transmission failure resulted in large amounts of metal or fiber contamination in the fluid.
The torque converter is a hydraulic device that couples the engine crankshaft to the transmission. The torque converter is a sealed, welded unit that is not repairable and is serviced as an assembly. The torque converter consists of an outer shell with an internal turbine, a stator, an overrunning clutch, an impeller, and an electronically applied converter clutch. The converter clutch provides reduced engine speed and greater fuel economy when engaged. Clutch engagement also provides reduced transmission fluid temperatures. The torque converter design has been optimized to be highly efficient and provide excellent launch feel and driveability throughout its operating range.
The Torque Converter Clutch (TCC);
- uses a three path lock-up clutch system.
- contains a dedicated apply circuit.
- contains a multi-plate clutch.
- piston is balanced.
- piston is isolated from the torque converter hydrodynamics.
- is equipped with a long travel torsional damper.
The combination of an advanced lock-up clutch system and long travel torsional damper extends the lock-up clutch operating range. This enables reduced lock-up clutch slip speeds, down speeding of the engine and slip control during transmission shifts. The benefits are improved fuel economy, excellent driveability and Noise, Vibration and Harshness (NVH) isolation.
OPERATION
| 1 - Turbine | 7 - Cover Shell |
| 2 - Impeller | 8 - Internally Toothed Disc Carrier |
| 3 - Stator | 9 - Clutch Plate Set |
| 4 - Input Shaft | 10 - Externally Toothed Disc Carrier |
| 5 - Stator Shaft | 11 - Turbine Damper |
| 6 - Piston |
The torque converter housing has a unique shape to incorporate the TCC and flex plate connection. The torque converter uses the typical turbine, impeller and stator assemblies found in a standard torque converter assembly. The torque converter drives the transmission pump. The turbine, which is fixed to the cover, imparts motion to the fluid within the torque converter. This motion causes the impeller to rotate. The impeller drives the transmission input shaft when the engine is running. A stator assembly is used to redirect the fluid flow from the turbine to the impeller to increase efficiency. The stator uses a one way clutch to allow rotation in one direction only. The TCC operation is managed by the Transmission Control Module (TCM) controlling the TCC solenoid located in the valve body. The TCM uses numerous inputs such as vehicle speed, engine fluid and transmission fluid temperature, engine load, throttle position and brake input to manage the TCC.