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'* 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.

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'* 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?

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.