I went on a road trip last weekend and got sick of a whining noise coming from the rear end. It's not that bad but still doesn't seem right. As far a my memory serves me the whine has always been there. The axle is a 3 year old Moser 60 True Trac 4,10 that's not been beaten too hard. I really would like to fix this. Or is the True Trac normally noisy? Any ideas?