intermittent mild brake pulsing
 

when I apply the brakes they frequently feel like they are not smoothly operating, not like the feel of warped rotors , but a general uneven sensation in the brake pedal. The front pads and rotors are new, but the problem is still there. The back ones were checked and found to be mechanically good, so I am wondering if it coulld be a bad wheel or something other than the brake components.

I suspect it is just that, warped rotors. Just because the fronts are new doesn't mean anything. Plus you can get the pulsing from the rears even if the fronts are fine. I have mild pulsing also.

I've had two other "H" body cars ('92 Buick LeSabre & '94 Olds Eighty Eight) and I had to pay close attention to the accuracy of the rotors. Since I have a lathe, I turned them myself and made sure they were within .0005" parallel and the same runout. This helped a lot, but then after a few heat cycles I could tell something had moved a little. It is probably due to the material the rotors are made of. It wouldn't surprise me if the 2000+ rotors are the same way.

I had the same effect. My fronts were just turned and pads were good. Ended up being the rear rotors. Try braking just with the emergency brakes.......if you get the pulsing then it's your rear discs. Replace the rotor and the pads.....easy to do and not that costly.....about $100 total for parts if you do it yourself.

I agree with Brian. Check your rear brakes - in particular the insides of the rotors. They often pit and can cause what you are experiencing.

Rear rotors
 

I had the dealer turn the rear rotors at about 34000 miles on my 03. I would have preferred he replace the rear rotors. it's back after about 15000 more.

Are the gM rotors just no good after awhile? So the rear calipers drag? I had that on the front on a 98. Replaced calipers, Raybestors best rotors, OEM level pads and it felt great.

Do the rear calipers need to be replaced? They're about $100 reman when i priced them.

What rotors? Cheaper ones from China? $70 Raybestos? $16 store brand which I think they said were Raybestos made? What choices have BC members made?

Pads? GM? OEM quality? Are the original GMs ceramic?

thanks for the info guys, I will do the rear pads and rotors myself because the Bonneville is currently not registered and I can do it whenever there is some free time. It's a 2004 SE and has 43000 miles on it. Other than the this I am fully satisified with the car. BTW the battery died on my wife's 98 SLE after 9 years. come to find out, the positive cable had a ton of corrosion on the inside of the boot cover. I cleaned it and replaced the battery and put the old battery on the battery tender. 8 hours later it was fully charged so now I have an emergency backup.

Jim you dont buy pads often so get the better ones. Everytime I have gone for the lowest price it seems like there are problems. Cleaning your negative ground to the body may help keep corrosion away as well. GM likes to bolt them right to a painted surface.