One-Speed Torque-On-Demand

WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.

The 1-speed torque-on-demand transfer case consists of the following components:

Mode Select Switch(MSS)
Transfer Case Control Module (TCCM)
Integrated Wheel End (IWE) solenoid
IWE s

The Borg-Warner 1-speed torque-on-demand transfer case is a 2-piece magnesium design. The transfer case transfers engine power from the transmission to the front and rear axles. Under normal driving conditions, the unit is in All-Wheel Drive (AWD), but when desired, the operator may shift into 4 wheel drive high (4H). The operator can switch between 2-Wheel Drive (2WD), AWD and Four-Wheel Drive (4WD) HIGH mode at any speed. The transfer case is equipped with an internal electromagnetic clutch and is shifted electronically. In AWD, the 4X4 control module varies the torque split between front and rear drivelines by controlling the transfer case clutch. Under most conditions, the 4X4 control module activates the transfer case clutch at a minimum duty cycle (percentage of time the clutch is turned on) which allows for a slight speed difference between the front and rear drivelines which normally occurs when negotiating a corner on dry pavement. When the rear wheels are overpowered, the 4X4 control module detects this slip condition and the duty cycle to the transfer case clutch is increased until the speed difference between front and rear drivelines is reduced. In this manner, the 4X4 control module can redirect engine torque to the front wheels when the rear wheels lose traction, yet still allow operation in the AWD mode on dry pavement. The unit is lubricated by a positive displacement fluid pump that channels fluid flow through holes in the rear output shaft.