problem with 4WD on 2004 F150 FX4
 

When actuating the 4WD unit getting grinding noise and won't go into 4WD-does anyone know what might be the issue?

This link will probably answer everything you need to know.
https://www.ford-trucks.com/forums/8...then-some.html

ok-thanks much-deer season upon us-may have to work on truck in a couple days-will check out the link

JFYI.....if you need the hub actuators, they are $62 on Amazon....same mfr and appear identical to the $120 and $180 units. The Solenoid I would go Motorcraft as well as the the check valves. Keep in mind if the actuators are worn down from grinding, there is something in the vacuum system that caused it so its important to find the cause before ruining the new actuator. I learned the hard way.