Wheel drive shaft
The wheel drive shafts are blocks of movable shafts that transmit torque from the differential cup assembly to the rear wheel assemblies.
Each axle block contains a universal internal and external constant velocity joint connected to the wheel drive shaft. The inner and outer hinges are fully movable, but cannot move in or out.
Cardan shaft
The cardan shaft assembly is a 2-piece construction. The front shaft consists of a CV joint of the type "A" front and universal joint and yoke at the back.
The rear shaft consists of a central bearing and a central fork, which are pressed into the rear half of the driveshaft and secured with a circlip. The front and rear shafts are combined in a fork using a universal joint. The rear shaft is connected to the axle with a flange, which is connected to the rear shaft by a universal joint.
The center bearing provides support where the front and rear shafts meet and is bolted to the underbody. Front CV joint bolted to power take-off (PTU), and the rear universal joint flange is bolted to the clutch assembly.
Rear drive unit
Rear drive unit (RDM) in this vehicle consists of a clutch controller and an aluminum crankcase that houses the clutch assembly and differential.
An on-demand differential distributes variable torque/power to the rear wheels via separate axle shafts.
The on-demand system works like this: only when the front wheels slip occurs, it distributes torque/power proportionately to the rear wheels. As long as there is no difference in speed between the front and rear wheels, no torque/power is transferred to the rear wheels.
When slippage occurs between the front and rear wheels, the clutch controller receives information from the ECM, BCM, EBCM, and the clutch controller sends a signal to the clutch assembly to actuate the clutch pack, which then distributes torque/power to the rear wheels. The torque on the rear axle is adjustable from 0-2,530 Nm, depending on such diverse road conditions as asphalt, sand, snow and ice. The torque distribution ratio between the front/rear axle is continuously adjusted to achieve the optimal value in the range of 100/0 ~ 50/50 in real time, depending on the vehicle's driving mode and road conditions.
The system is equipped with a built-in protection device that reduces rear wheel torque when excessive heat is generated, thereby protecting the rear wheel drive unit (RDM).
Rear differential fluid assembly
The rear differential assembly uses a specially formulated synthetic hypoid fluid designed for lifetime service. However, proper fluid levels must be maintained to ensure proper operation of the rear differential assembly.