Wheel Hub: Description and Operation

Integrated Wheel End (IWE) System

The IWE system consists of the following:

- Vacuum reservoir
- IWE solenoid
- IWEs (spring-loaded vacuum hubs)
- Vacuum hoses
- Check valve

The IWE system uses vacuum hubs that engage the front wheel hubs to the front halfshafts or disengage the front wheel hubs from the front halfshafts.

The IWE solenoid receives engine vacuum from the vacuum reservoir.

When the 4WD system is in 2-Wheel Drive (2WD) mode, the 4X4 control module supplies a ground path to the IWE solenoid to apply vacuum to the IWEs (disengaging the front hubs from the front halfshafts). In 4WD mode, the 4X4 control module does not supply the ground path to the IWE solenoid, vacuum is not applied to the IWEs and an internal spring keeps the front hubs engaged to the front halfshafts.