Hello everyone this is my first post and i need some help

I was in my wife's 05 fx4 150 today and i heard a avery loud grinding noise, sounded like it came from trans or front diff,lasted for about an eigth mile until I stopped. It seemed like there were gears trying to engage and it did not quit until I stopped the truck then there was a quiet clunk, like everything connected back up. Kinda hard to explain any help would be appeciated so I can give the dealer my opinion,since they think nothing is ever wrong. (30000 miles)

 

just searched this site a little more looks like it is the IWE

 

If it does it again try turning 4x on and off. If that makes it go away immediately then probably the IWE.

 

I know exactly what that is. Your 4x4 hubs are trying to engage because you have a vacuum leak. Go to Ford and have them look inside the right fender well and see if your vacuum tubes have made contact with your headers anywhere. Apparently this is a common problem due to the routing of the vacuum hoses in 4wd F150's.