New rear end
 

My 2007 Chevy Silverado 4x4 LT HD is making a roaring sound in the rear end. Unfortunately it was noticed 3 days after my extended warranty ran out.
I tried an additive in the rear end which did quiet it down for a few weeks but it is now just as loud and getting louder. I did notice a few shavings in the gear oil.
I am planning on replacing the gears myself and was wondering the easiest way to go about this. Any suggestions are appreciated. I have extensive knowledge in mechanics but haven't been working in that field for a number of years.