rear axle

Last week while driving (1996 Tahoe) to Petaluma I suddenly got a noise out of the right rear that sounded to me like a bearing. I still haven't taken anything apart, waiting to learn more about what I am getting myself into. It should be an adventure. If it is the axle bearing, it is available...

i have a 2000 tahoe with rear drum brakes and would like to know if there is a rear axle from a newer tahoe with disc brakes that would have the same demensions, for a quick swap?