I have a '98 Pontiac Transport. Wife has been noticing a sound when she brakes so I looked at it. Pulled th PS rear wheel and drum and found the entire brake assy is covered in grease. I assume that this is from the hub and wheel bearing. Haynes says this is a sealed unit which must be replaced. Has anyone done this? Is it a big job? I can do pretty well with mechanical work and have always replaced my own brakes and some trans axles on a Honda. Any hints to make it easier?