I have a strange noise comming from the front axle. Truck is a 2005 Chev 2500HD Duramax 4/4---90000 miles----the noise is like an engine rattle as if it is out of oil ( as if you drained the oil for an oil change added new oil but it takes a minute to get to the bearings). It is noisey at both low speed and high speed. When i put it in 4hi the noise goes away. The noise is like a bunch of marbles rolling around in a can..Any advice would be helpfull.