Not me but a colleague at work has horrendous brake squeal on his rear brakes. I told him last week to clean his bike, rims, etc. He's still got the problem so I take a look at it today and the whole back wheel is covered in gunk, etc. as he does a 10 mile commute through the city and it has been raining a lot this week. Anyhow, cleaned it up and not resolved. I asked him what he cleaned it with, and it would seem he used some form of lubricant. He said this worked at first (!) but then the squeal come back. I'm fairly certain the pads will be contaminated and will need replacing. Is this a reasonable conclusion? I see Mickle said this for the same problem on a different post.