allroad-Ed

Put some new pads and rotors on the front of my allroad last week. Had issues getting the old rotors off but finally got it taken care of.

The brakes are squealing like mad now...after 2-3 stops (to warm up the pads/rotors I assume) the brakes squeal very loud when I come to a complete stop...they only squeal at the very end of braking when the car is stopping. If the brakes cool off a while they do not squeal again until they warm up after 2-3 stops.

I'm using Zimmerman slotted/drilled rotors with PBR Ceramic pads.

I put anti-squeal grease on the outside pads - the inside pads that go directly against the pistons did not really have any place to put the grease.

The guy that helped me put the rotors on saw the grease on the pads and said that I had "glued the pads on"...he said it would cause my squealing. I did not use glue though, just anti-squeal grease from Kragen called CRC Disc Brake Quiet:

<a href="http://www.partsamerica.com/ProductDetail.aspx?categorycode=3223&mfrcode=CRC&m frpartnumber=05016">http://www.partsamerica.com/ProductDetail.aspx?categorycode=3223&amp;mfrcode=C RC&amp;mfrpartnumber=05016</a>

The new pads squealed with my old rotors for 100 miles or so and then I got the Zimmerman's on and they still squeal after 800+ miles.

I did follow a "bed-in" process to break the pads in with my new Zimmerman rotors...plus put 800 miles on after that.

Any ideas? Should I dump the ceramic pads and buy some Mintex Red Box pads? I hate to throw out the new PBRs and spend more money on this car that's bleeding me dry!

QCRAZY

PBR's shouldn't do that...those are what I use a lot. How exactly did you "bed" them??

allroad-Ed

Well...I did the bed-in twice...

Since I could not get the old rotors off the first night, I did a bed-in then with the old rotors. Then, about 100 miles and 1.5 days later, I did another bed-in right when I got the new rotors on. Here's what I did both times:

Accelerated up to 60-70 MPH and then hit the breaks hard, slowing to 10-20 MPH as fast as I could without completely locking up the brakes/engaging ABS.

I did this about 8 times and then let the brakes cool by driving around a bit.

So...maybe I need to do 2 or 3 more sets of that procedure (8-10 times each set)?

Funny thing is, even after heating them up like that, they did not squeal. But the next time I drove the car, and every time since, as soon as the brakes get warm they squeal when the car comes to a stop.

I read a long post in this forum about sanding my rotors and pads...seems like a lot of work...am hoping I can just try harder on the bed-in...

Ex-PzKW Cdr

like slaughtered pigs, they also have lousy friction coeffecients.. I like the Mintex. Use CRC or Permetex spray on disc brake quiet, and put it on THICK!!!(only on the steel backing plates, I have seen people spray it on the friction surface) Also either replace or resurface your rotors, .03 ipr feed, and use a cutoff wheel sideways in an up and down fashion to produce a Non Direction finish on the rotor. Wire brush all the crap off the caliper anchors and switch them left to right. Lube the pad contact points with synthetic caliper grease, DO NOT get any grease on the pads or rotors, this will produce carbon spots and will make a squeel. I don't like PBR or EBC, I have had problems with both. Mintex can be problematic on occasion if rotor surface prep is not looked after. Also lube the caliper pins with synth grease after cleaning them.

allroad'Ed now

I did NOT bed in per their recommendations. I bedded like a race pad. However, I can get the Redbox to fade under repeated hard braking on the street. They would be absloutely worthless on the track.

QCRAZY

Sounds like you glazed the pads...get the sand paper.

allroad-Ed

Do you think I can just sand the pads, or do I need to sand the rotors as well?

Rally_nutcase_1982

Pads only, never sand the rotors, they would need to be machined, but not really necessary now.

allroad-Ed

Will try that...

Regarding sanding the rotors...this post made me think of that:

<a href="https://forums.audiworld.com/allroad/msgs/132925.phtml">https://forums.audiworld.com/allroad/msgs/132925.phtml</a>

So sanding or scuffing the rotors is not a good idea? Sounds like a pain so I'll just stick with the pads.

- Ed

Rally_nutcase_1982

in this linked message. Because you've just installed the rotors there is really no need to treat them after only a few miles.
Remember, my pads went sour on the way to VIR, I still took it on the track, drove another 500 miles back home before I put on Porsche OEM pads - not treatment for the new rotors, just bed in for the new pads and she stops on a dime again ;-)

Putting on new pads will do a little job on the rotors and "sand down" some of the markings, the same as spending a couple of hours with Sandpaper, but 100% more even and equal then you'll be able to do.......just a thought...