4WD SYSTEM OPERATION
BUE031866602N02
• On front drive transaxle vehicles, a transfer case unit has been equipped to transmit power to the rotary blade coupling (RBC) installed to the rear differential through the drive shaft and universal joint.
• There are two 4WD lock switch positions, AUTO and 4 x 4 ON. In the AUTO position, the vehicle travels in 2WD unless the front wheels slip. If the front wheels slip, a difference in rotation speed between the front and rear axels occurs, and the rotary blade in the silicone fluid rotates. Rotation of the rotary blade produces pressure in the silicone fluid. Based on this pressure, the piston is pressed, the RBC clutch plate engages, and torque is transmitted to the rear wheels. The amount of torque supplied to the rear axel is based on the difference in vehicle wheel rotation speed between the front and rear wheels. At the point where there is no front wheel slip, the drive system returns to 2WD.
• The 4 x 4 ON mode locks the RBC using the built-in magnetic clutch to transmit power to the rear wheels from the rotating drive shaft. In 4 x 4 ON mode the vehicle travels in 4WD unless the switch position is changed.