I have changed my rotors and brake pads on my is200 05', but have a small noise when i apply the brakes when they are hot. I have not changed the shims, could that be the culprit? sounds like the sound is coming from the rear wheels.

I did put allot of copper grease on the outer end of the shim...should i try putting some copper grease between the shims and the brakepads aswell before buying new shims?

Best regards
Robin A.