I have an 04 Grand Prix GT N/A 180k miles. Occasionally when breaking at slow speeds I hear a bad growling noise coming from the left front brake. I can also feel through the pedal a shifting or movement. The left front rotor is on average 50 degrees hotter than the right.
I have new rotors, pads, and calipers also wheel hubs are new. The brakes have been bled a couple times. I do not think any parts are defective. I replaced the caliper twice.
My theory is maybe 2 problems. I did not change the rubber brake lines because the fittings are pretty rusted and they will probably break or twist. I hear they can go bad from the inside out and cause the piston to not retract? Is that true? and maybe the movement I feel is suspension related such as sway bar or control arm bushings. Or maybe it's ABS related? no lights on though.
I know my way around a car pretty well but this has me stumped.
Thanks to all for any input.