Transfer Case: Overhaul: Description

The Ford Motor Co. transfer case is used to engage rear drive axle operation at operator's selection. This single range unit provides 4WD under all operating conditions. Selection is controlled by a dash mounted All-Wheel Drive (AWD) switch.

Selection of the All-Wheel Drive (AWD) switch controls operation of the rear drive axle. When the AWD switch is turned to "ON" position, electrical current flows to a relay activating the 4WD solenoid valve. Activation of the 4WD solenoid valve allows vacuum to be created in the left chambers of the vacuum servo.

Vacuum application to the left chambers moves servo rod and sliding collar into engagement with output gears. Sliding collar engagement provides rear drive axle operation. When the AWD switch is turned to "OFF" position, electrical current is applied to the 2WD solenoid valve. Activation of the 2WD solenoid valve allows vacuum to be created in the right chambers of the vacuum servo. This vacuum application disengages sliding collar, releasing power force to the rear drive axle.