I've had squealing brakes on my 8.3 as well, both front and back.I would wipe the rotors with alcohol and it would help for 10 minutes or so. The lbs I bought it from talked to Trek and they sent a softer set of pads to try and it has helped a lot.It hasn't stopped it but it's more random. I haven't been riding it near as much since I got a roadbike but with winter weather coming I think it'll see much more action.