Thanks for the good advice and ideas, I wish I had run this up the flag pole before it went to my mechanic. He's thorough but not a break specialist. He did regrease the caliper slides (good call) due to the passenger side wearing not square and more than the drivers side. But did not resolve the problem. He also clamped the quarters but may not have had the knowledge to identify the problem area. I'll send him your comments to see what he says prior to moving on.
Keep on vanin.