The following is a little information in hopes that it might increase understanding of how the AWD function in the vehicles work. This is not intended to be used for problem diagnosis or repair, but mainly as an interest in some high level system components and functioning. Replacement or maintenance on this system should only be performed by qualified personnel and in some cases may need reprogramming which can only occur with dealer specific diagnostic equipment.
Summary
The center mechanism is referred to as a "Power Transfer Unit", and it connects engine output to the rear axle. From there, the rear differential contains a computer controlled clutch mechanism. The last part of the system is a traction control system which will help to route power to a wheel that has traction if slippage occurs.
Details
Front mechanism:
Rear Mechanisms:
Controlling Mechanisms:
All of this is all controlled through inputs such as wheel speed sensors, transmission and engine information and even steering wheel angles through multiple control models:
From the owner's manual the following is found on page 203:
This is quite technical but should help us feel comfortable that this is a system that appears to be on par with most systems on the market.
Summary
The center mechanism is referred to as a "Power Transfer Unit", and it connects engine output to the rear axle. From there, the rear differential contains a computer controlled clutch mechanism. The last part of the system is a traction control system which will help to route power to a wheel that has traction if slippage occurs.
Details
Front mechanism:
The power transfer unit (PTU) is positioned in the right side of the vehicle and bolted to the transmission via an adapter plate. The primary function of the PTU is to receive power from the transmission and transfer it using helical and hypoid gear sets through the propeller shaft to the rear differential.
Rear Mechanisms:
The rear differential clutch control modules function is to control the electronic open differential. The rear differential control module calculates torque command internally according to the driving situation to achieve vehicle dynamics and traction. The electronic differential system contains the following main components:
When the torque signal is received, the rear differential control module actuates the following components:
- The rear differential clutch control module
- The rear differential clutch motor
- The rear differential multi-disc wet clutches
- The rear differential clutch motor
Controlling Mechanisms:
All of this is all controlled through inputs such as wheel speed sensors, transmission and engine information and even steering wheel angles through multiple control models:
From the owner's manual the following is found on page 203:
For a preview of the system in action, the following uTube video does a fairly good representation:The AWD system delivers power to all four wheels and the system adjusts as needed to improve traction.
This is quite technical but should help us feel comfortable that this is a system that appears to be on par with most systems on the market.