I recently purchased a '03 Z71 silverado w/ 4 wheel drive. While out in the mountains I had the chance to use 4wd (4 hi) but noticed what sounded like a grinding or rubbing noise coming from the front end, more pronounced when turning or accelerating. The noise was not constant, but was matched to the rotation of the wheels. It was similar to the sound a worn out brake pad makes against the rotor. I am going to take it to the dealer to have it checked out but wondered if anyone had any ideas what could be causing this. The noise is gone when in 2wd, and the truck performs great otherwise.
thanks much