Mercedes automatic transmission torque converter lock
The torque converter in a Mercedes automatic transmission is used to transmit torque from the engine to the transmission. It consists of three main elements:
* pump wheel attached to the engine
* turbine wheel attached to the transmission
* stator located between the pump and turbine wheels
When the engine is running, the pump wheel drives the turbine wheel through a fluid called transmission fluid. The difference in speed between the pump and turbine wheels allows the torque converter to transmit torque.
Torque converter lockup
The torque converter lockup is a mechanism that connects the pump and turbine wheels, thereby eliminating slippage between them. This improves transmission efficiency as it reduces energy loss due to slippage.
The Mercedes automatic transmission uses an electronically controlled torque converter lock-up. The transmission’s electronic control unit (ECU) controls the lockup operation using a solenoid valve. Under certain conditions, such as cruising speed or acceleration, the ECU activates a solenoid valve that mechanically connects the pump and turbine wheels.
Benefits of Torque Converter Lockup
* Improved fuel economy
* Improved dynamic performance
* Reducing transmission fluid temperature
* Increased transmission life
Torque converter lock-up faults
Damaged or malfunctioning torque converter lockup can cause the following problems:
* Slipping or vibration at certain speeds
*Lower power or poor acceleration
*Transmission overheating
* Increased fuel consumption
If you suspect your Mercedes is having torque converter lockup problems, it is important to have it diagnosed and repaired by a qualified mechanic.