I have a brand new F150 that has developed a metalic grinding sound in the front. It only occurs when I am moving. It will go away if I shift into 4-high then come back later. Naturally, I can not make it do it at the dealer service dept.
Take a tech WITH you for a test drive next time. Show him what you do to start/stop the noise.
A brand new (2008?) 4x4 (possible transfer case fault) shouldn’t be making any weird noises.
I hope you haven’t been using the 4 wheel drive on dry pavement.
[b]It sounds like one of the front hubs isn’t fully disengaging. When this happens, you’ll get a grinding noise from one of the front wheels.