Typically, in a 2WD mode (or when the system determines it's not needed), the transfer case directs power only to the rear wheels. This effectively disconnects the front driveshaft by not sending power to it. It doesn't physically disconnect the shaft but rather electronically prevents power transfer.
If you're experiencing problems:
* Check the 4WD indicator light: If it's flashing or malfunctioning, there could be a problem with the system preventing the proper disengagement. This points to a potential issue with the transfer case, wheel speed sensors, or related wiring. A diagnostic scan is recommended.
* Listen for unusual noises: Grinding or binding noises while driving in 2WD suggest a problem with the front driveshaft or related components (CV joints, etc.) even if the system is electronically disengaging.
* Professional diagnosis: If you're experiencing issues with the 4WD system (either engaging or disengaging), a professional mechanic with experience in 4WD systems is necessary to diagnose and repair the problem. Trying to force a disengagement when it's not functioning correctly could cause damage.
In short, there's no manual way to disengage the front driveshaft on a '95 Aerostar. It's an automatic system that should disengage itself when 4WD isn't needed. Any issues require professional attention.
