Front Drive Axle Description and Operation

Selectable Four Wheel Drive (S4WD) Front Axle Description and Operation The Selectable Four Wheel Drive (S4WD) Front Axle consist of the following components: Differential Carrier Differential Assembly Drive Axle Clutch Sleeve Electric Motor Actuator Inner Axle Shaft Housing Intermediate Axle Shaft Wheel Drive Shaft – Left Wheel Drive Shaft – Right The front axle on a Selectable Four Wheel Drive system uses a central disconnect feature in order to engage and disengage the front axle. When the driver engages the 4WD system, the Transfer Case Control Module sends a signal to the electric motor actuator to energize and extend the plunger inside. The extended plunger moves the clutch fork and drive axle clutch sleeve across the intermediate axle shaft and the wheel drive shaft and locks the two shafts together. The locking of the two shafts allows the axle to operate in the same manner as a semi-floating rear axle. A propeller shaft connects the transfer case to the front axle. The differential assembly uses a conventional ring and pinion gear set to transmit the driving force of the engine to the wheels. An open differential allows the wheels to turn at different rates of speed while the axle continues to transmit the driving force. This prevents tire scuffing when going around corners and premature wear of internal axle parts. The ring and pinion set and the differential are contained within the carrier. The axle identification number is located on lower left of the differential cover. The front wheel drive half shafts are completely flexible assemblies consisting of inner and outer constant velocity CV joints protected by thermoplastic boots and connected by a wheel drive shaft.