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Discussion Starter #1
I've had an annoying rotor shudder that I can trace back to an emergency stop I had to make back on a scorching day in August. I've just lived with the shudder, but last week I put two and two together and now think this is a case of pad material transfer to the hot rotor.

I'm a relative newbie to working on my brakes. Can anyone give me some input from their experience?
 

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I have had a lot of brake related problems, just minor stuff like this shudder you are talking about. I would first consider taking the tires off, inspecting the front brakes. Take the caliper off, look at the rotor, inspect the pads. Then clean the slides with a wire brush well. Use brake clean and blast the rotors with that. Lastly I would take some very fine grit sandpaper and scuff the pads and the rotor lightly with that. But her back together the rightway.

Sometimes a simple thing like this can eliminate 80 to 90 percent of small queals, shudders, knocks, etc. I've some strange problems where one pads was not right and it threw out the whole operation making the car stop like crap.

If something like this won't fix it, I'd suggest attempting to turn the rotors (if they have low miles), or just buy all new pads and rotors and install the right way the first time and you should be good to rock at that point for a long time.
 

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I am assuming you have a little bump and kick in the brake pedal that you can feel in your foot when you are trying to stop.

I have the same thing currently, my rotors are Bendix (I think) they are 3 years old and I live in Ohio where winter weather and salt kills cars that don't recieve regular washings. (as you probably experience from living up in Vancouver)
 

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Discussion Starter #4
Thanks! I have that exact bump and kick you describe. I can live with it, but I worry that it will compromise braking when an emergency situation arises again

So would a wire brush attachment for a power drill be too agressive for cleaning?
 

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Are you sure its the brakes? In this emergency stop you mentioned did you lock up the wheels. If so you could have flat spotted the tires which can have the save feeling you described under subsequent braking as well. Not a whole lot you can do to correct this if it occurred.

To clean the rotors up it might be better to take the them off and have them "dressed". Dressing is where they put them on a brake lathe and just clean up the surface, you're not doing a full truing (unless its really needed). Someone at an auto machine shop (or a race shop as they do this frequently, especially the low budget circle track boys) would probably be more willing to do this than the local auto parts store.
 

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If your rotors got to the point where you can feel pedal pulsation.....you're probably past the point where "dressing" the rotors will help out. Sounds like turning the rotors is called for (or replacement).

You can actually "dress" or clean up the rotors on the car by hand. Support the car well with the front wheels off the ground.....remove the front wheels, and run two nuts down to hold the rotors tight. Have a helper run the car in gear, while you clean up the rotors using sand-paper. Works.....I've done it plenty of times.

Rotors are fairly cheap for the Focus.....hardly worth messing with.
 

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Discussion Starter #7
I didn't lock up the wheels luckily and I only feel the pulsing upon braking.

If I took the front wheels off would I see anything in the way of pad material on the rotor, even a dark patch?

I will retourque the wheels while i'm there.
 

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Discussion Starter #8
From a cursory inspection, I couldn't see anything out of the ordinary other than a few tiny imperfections the size of a pin head that felt ever so slightly raised. With all the salt on the roads these days, could just be crud from the road. Will try and get to a shop in the next little while and live with the pulsing for now
 

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my guess is you have too many miles on the rotors and they are warped, just get new rotors.
 

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Discussion Starter #10
Strange thing is that they only have about 16000 km on them
 

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ya, thats pretty low, i don't think its the rotors then.
 

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yes...when I put my new pads on, they didn't come with shims built into the design of them and they shuttered pretty bad. once i bought some shims, the problem went away
 

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Discussion Starter #15
hmm, I'll do some searching...

I have Brembo rotors and Hawk HPS pads. The local Focus guru who installed them has had no problems with this setup. I've also heard this is a good solid setup for the DD. That being said, I know fairly little about the subject, so who am I to say :)
 

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Did you bed in the pads correctly after installing them.

Since your hard stop, have you done any major braking since then?

If I every get any build up like this, I'll do a few harder stops and then drive around for 15-20 minutes at lower speeds with minimal braking to let everything cool down before parking the car. My hard stops are 20mph and slamming on the brakes, sometimes I'll ride the brake for 50-100 feet gently to clean everything off. I don't have any shudder with my car and the setup on it.
 

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Discussion Starter #17
They were bedded properly and I ran things easy for the first 500km. That was the hardest stop on these pads/rotors

Hey that's a good suggestion. Basically free and more pleasant than taking off the wheels in this chilly weather, even in a slightly warmer garage
 

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Discussion Starter #18
I had a good romp on the brakes the other day, but it's been so icy here that i've not been out driving much. Add that to an f'ed up back and I've not been doing much of anything :( !

will keep you updated ...
 
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