It is Camaro 1987 with 5.7 ltre engine with four wheel disk brakes. Installed new rotors and pads all ACDelco parts after few hundred miles developed squeak from rear a low speeds. I have checked the brakes to see if something is out of place. Nothing is visible. Need help please?

Are the calipers hanging up at all?

Did you use and de-squek on the moving components?

The slides and calipers are good. I believe that it can not be brakes but that the brakes change the noise. which could be drive line or diff noise the car has low miles but has age. this almost sounds like high pitch pinion noise.