Loud clunking/ No Power
 

2005 Silverado 1500, ex cab, reg bed, 2wd, 4.3, G80 10 bolt.
As I was driving I noticed a loud clunking noise with some tug, getting louder and louder especially during turns. Then the truck would go from driving with the loud clunk too loosing power to the wheels. The drive shaft would just spin with the noise getting worse and worse in order to get it home from my work I had to have it at idle speeds in order for it to engage and drive. Of course after every turn it would loose power to the wheels and I had to go through the process of trying to get it to go at idle speeds all over again. I pilled off the diff cap, fluid burnt nasty, but no metal shards or teeth knocked out. Next took off my driver side rear wheel the self adjustor was snapped in half and cracked the wheel piston. I thought that may of been the cause of the noise. With it on jack stands I started it and the noise continued. Then when I threw it into N too stop it, the wheels were still powered then once I stopped them by wedging a cheater bar between the studs, it would stop then continue again. With the noise persisting. Any ideas? Axel shaft? The tranny should be fine fluid is still red, not burnt at all only noise from it ever was the 1st/2nd shift as always with em.