Over the last year and a bit i have had my front brakes and rotors done, and my drivers front wheel bearing done. When I first start driving I don't have any issues, say 20 mins, but after that I can hear my brakes rubbing like they are catching. It's intermittent . I have taken it to a mechanic and they seem to think it maybe the calipers due to temperature. I'm in ontario canada and the heat has been hot in the day and cool at night. i have noticed when i leave in the early am of leaving for work that i dont hear anything. Any thoughts would be greatly appreciated.