New to the forum

I just purchased a 2012 F150 4x4 with 32k miles. On the highway at cruising speed I noticed a slight vibration especially in a slight curve in the road turning to the right.
I had the chance to lift the truck off the ground today and found that the drivers side half shaft was not turning when I spun the wheel. This seemed normal.
However, the passenger side half shaft did turn as I spun the wheel so I'm assuming this is where the vibration is coming from.
I'm guessing my passenger side wheel hub is not disengaging but I'm not sure what to look at first to make repairs.
Any help is appreciated.

Thanks a lot.

 

Welcome. Sounds like either vacuum has been lost to that side or the IWE is seized.

 

Thank you,
To understand how the unit works, in 2wd the solenoid is closed with no vacuum applied to the axle or is it the opposite?
Or in other words,
If I check vacuum at the hub in 2wd should I have vacuum, or should I not have vacuum.

Thanks for your help!

 

 

Thanks so much for the help, the video was especially helpful.

I took it apart today and found the plastic ring that holds the actuator cracked thus not allowing it to seal.

Replaced the actuator and everything is back to as it should be.

Thanks!

 

Good deal