Help, I have a horrible howling sound that sounds like it is coming out of the middle or rear of the truck, sounds like tires rubbing, or the chain in the x-fer case (208)? Could it be the rear axle (10 bolt)? It does not make the sound all the time, just often, then it will just go away, usually after I stop to let a friend out to listen. Then a few miles down the road the howling starts again, goes along with the revolution of the tires. Checked the tires and they are not rubbing anywhere. '84 K5 Chevy in my blood.