Transfer Case
The twin speed transfer case is an on-demand AWD system with compact chain and sprocket which provides a compact and low weight design. The transfer case includes a multi-plate wet clutch, with electro-hydraulic actuation. The transfer case is controlled by the TCCM , which automatically controls the amount of torque being transmitted to the rear and front axles.
The TCCM monitors inputs from other vehicle systems. These inputs include:
- Wheel speed
- Steering wheel speed
- Yaw rate
- Torque supplied from the engine
- Position of the acceleration pedal.
Using these inputs, the TCCM calculates and delivers outputs to the pump actuator and solenoids. The pump actuator in turn, provides pressure to the multi-plate clutch to distribute the required torque between the front and rear axles. The AWD lock solenoid changes the drive style between AWD and Rear Wheel Drive (RWD). The clutch actuation solenoid changes the range state between high and low.
The twin speed transfer case system provides continuously variable response, with high torque accuracy to provide exceptional dynamic performance.
The twin speed transfer case also improve fuel economy by providing only the request amount of torque to the front axle. If necessary, full locking torque is available at any given time and vehicle speed, depending on road conditions and vehicle load distribution.
The twin speed transfer case incorporates a pump-less lubrication system with active sump management. The pump-less lubrication system comprises a lower sump and an upper sump. The drive chain that transfer torque to the front axle also transfer oil from the lower sump to upper sump. Oil in the upper sump lubricates the clutch pack, bearing and upper seal.
the active sump management system also has the added benefit as following:
- The omission of the an oil pump
- Enhancing the fuel economy by reducing drag losses in the transfer case.