Pulsing Brakes

[pforwell]

Hi all,

I have an 05 Mazda3 GT HB.

I bought this car in August and sold my 99 Protege. I moved to Burlington in May.

At the start of June, my Protege started with this insane brake pulsing/car shaking when braking(especially at high speeds) so I had the rotors done. Sure enough, a week later it happened again. I had the rotors done under warranty thinking maybe DOA. A week later, warped. Finally it was determined that the hubs were out quite a bit and that was causing the rotors to warp.

Anyway, I bought a 3 in August as I needed something a little newer with less K's. I got the car and the rotors were fine... they warped about 3 weeks later. I had them fixed. They were good for 2 weeks, and now it's starting again. :flaming

I don't believe I've changed any of my driving habits... what in the world could be causing all of these rotors. I haven't even put 5k KM on the car yet.

Any ideas? I'm open to all ideas and theories as this is starting to get costly and more so just incredibly frustrating.

Please help!

[Donutz]

Are you sure it isn't the rotors? I would suggest getting your tires inspected, wheels balanced, and new rotors. Do you tend to be hard on the brakes, and hold the pedal firmly after stopping?

*edit - try bedding your brakes first. You might have inconsistent build up of pad material on the rotors.

[pforwell]

It probably is the rotors. It has been the last 4 times. I want to know what's warping the rotors. I don't believe any of my driving habits have changed and I drove my protege for over 2 years with not one brake issue. Then all of a sudden I go through 4 sets of rotors in as many months.

I don't think I'm hard on the brakes, I like to use my downshifting as much as possible and I'm not doing any really hard stops or anything. When I'm at a light I usualy just hold them hard enough to prevent the car from moving, I'm not pressing at all. Just the weight of my foot. (I may have a figurative lead foot, but not literal)

I will try bedding them. It could be the issue, but I'm just a little perplexed as to why these rotors keep warping so easily. I have not changed my driving style, however, I am doing a ton more highway driving than ever before... could that be an issue?

[SonicBoy]

Are you or the garage using a torque wrench to tighten the lug nuts on your wheels?

Too tight can cause warping under hard use however it doesn't sound like you are driving it hard.

Just something to through out there as this is most bizzare.