The brakes on my Pontiac Gp were thumpimg when applied. I took the car to my mechanic. He checked them out and said the 4 rotors were rusted but the pads were stil ok. So, he turned all 4 rotors. The thuimping is gone but now the brakes are no as good as they were. You have to push harder on the pedal and it seems it takes lomger for the car to stop. I would appreciate some thoughts on what would have caused this.

Replacing Rotors Because Of Rust, But Determining That The Pads Are Still OK Is Puzzling. The Rust Caused The Rotors To Thump Against The Brake Pads Wearing Them Unevenly, I’m Quite Sure.

The old pads are probably not contacting the new rotors over their entire surface areas because the old rotors wore them unevely. The excessive pedal pressure problem may improve a little as the pads wear-in, but it’s too bad that new pads weren’t installed with the new rotors. The old pads won’t do justice to the new rotors. Had your mechanic installed new pads, I’d bet you wouldn’t be complaining about pedal pressure, but maybe cost instead.

Your mechanic may have been trying to save you some money, but the brake job was compromised.


I agree. The old brake pads were probably glazed and glazed means they don’t “grip” the rotors. Gripping is where it’s at with brakes.