Brake Problem

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Jan 15, 2004 | 02:41 PM

KM9V

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From: Beaumont, TX

Brake Problem

I've got a brake problem that I can't figure out. My brakes were pulsing or wobbling. I replaced the rotors (which the brake guy said were warped) w/ cross drilled ones & new pads. But I still get some pulsing. My tires are balanced & rotated every 7500 mi. Here's the wierd thing, it doesn't happed all the time. It happens more when the brakes are hot/stop & go traffic. Hard braking doesn't pulse hardly at all. Could it be the master cylinder? Could there be air in the brake lines?

Jan 15, 2004 | 03:02 PM

trackbird

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Could be a byproduct of the drilled rotors. But, it is more likley to be caused by pad build up around the holes in those rotors or on the surface of the disc. The buildup will cause uneven friction and if it is heavy enough, it can cause a slight pulsing of the pedal (the buildup makes the rotor thicker).

My thoughts.

Jan 15, 2004 | 03:47 PM

KM9V

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The pulsating started almost imediately after the new rotor & pad install. I just checked, the rotors look clean.

Jan 15, 2004 | 04:42 PM

trackbird

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It only takes about .004 of an inch of pad build up to be noticeable during use (but very hard to see). I'm not sure a visual inspection would reveal the levels of build up we are talking about.

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Jan 15, 2004 | 04:45 PM

trackbird

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Quote:

Originally Posted by KM9V

The pulsating started almost imediately after the new rotor & pad install. I just checked, the rotors look clean.

I've seen brand new, warped, rotors. You may have a set that is warped from being stored vertically (standing on edge) or a manufacturing defect.

I worked at a parts store that stored rotors vertically (though we advised them to do otherwise). Most rotors that were there for any length of time and then sold, came back as "warped" when brand new. Just a thought.