4HI Mode Active Power Flow

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Fig 1: 4HI Mode Active Power Flow Components

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Input Shaft
2	Control Actuator Lever
3	Clutch Pack
4	Drive Chain
5	Rear Output Shaft
6	Actuator Shaft Gear
7	Front Output Shaft
8	Actuator Cam

Fig 2: 4HI Mode Power Flow

Courtesy of GENERAL MOTORS CORP.

During the Auto 4WD mode, the power flow is the same as it is in the 4HI mode. Except, during the Auto 4WD mode, the 2/4 wheel drive actuator assembly (13) rotates the control actuator shaft to the correct torque level positions. Rotating the control actuator shaft to the various positions changes the clutch torque level. When a difference of front wheel speed to rear wheel speed is recognized, the transfer case control module commands for more or less clutch torque.