Grinding noise when breaking at low speeds- please help.

Hello, I own a 2000 Pontiac Gran Prix (automatic). Recently I have noticed a grinding sort of noise when braking. It is audible from 15 mph or so but very noticeable under 10 or 5 mph. I am also able to feel vibrations on both passenger and driver sides. The car has appx. 111,000 miles on it, and I have recently had the front brake pads, rotors, and wheel bearings replaced. Also, the noise does not appear everytime I brake, and I have noticed it seems not to appear until the car has been warmed up a little, for it sounds normal for the first few stops.
Any input would be greatly appreciated, and if possible, please note whether you think this issue is serious, and possibly what the cost of repair might be around. Thank you all very much !!

 

did the mech who repaired the front brakes also check the rears? this needs to be checked out asap and repaired before it ruins expensive parts. the cost of repairs will vary greatly depending on exactly what the grinding sound.

life begins when the kids leave home and the dog dies.

 

I don't believe he did check the back brakes. Other than the rotors, what could be ruined if the problem is not fixed soon? thanks alot

 

the rear rotors could be ruined also, could cause brake failure. if your mech didn't check the rears when doing a front you need a new mechanic. IMO

life begins when the kids leave home and the dog dies