05 f-150 lariat 4x4...
for the past month or so my truck has had a scratching noise coming from my front driver side that sounds like my caliper/brake pads/something with the brakes... but its not anything to do with the brakes because i went to my deer lease this weekend and found out the hard way my 4wd doesnt engage or work. so when i got back on the road it started doing the scratching sound bad so i kicked it into 4x4 high and it immediatly stopped. so it has to do with the 4x4 i believe. any one with any idea of what this could be it would be greatly apprecitated.

or if someone could tell me how our 4x4 works and all that good stuff and give me something to go on...im not a mechanic but i can and have turned a few wrenches.

sorry for the long post but i wanna get this fixed. thanks guys.

 

WTF is this "search" thingy?

http://www.ford-trucks.com/forums/836438-everything-you-wanted-to-know-about-the-iwe-system-and-then-some.html