One of my customers has a 03 auto coupe with AP racing 4 piston front brakes on his car on they squeak like CRAZY!. Has anyone else had problems with this?? He's had the rotors turned and i've added anti-squeak to the pads twice. He's called stillen and of course they say they.ve never had problem's with this. He really wants to get the rear brake set-up, but doesnt want to have 4 squealling brakes. any advice??

 

I also have a customer will the AP 4 piston front and back and i was driving his car the other day and his front brakes were squeeking a little bit, nothing major though.

 

What pads his he running with em?

 

Did you have custom made noise reduction shims made to correctly match pad materials..............the oem brake engineers spend millions in this area alone.

Squeel usually from vibration from uneven forces across pad face.
http://www.automotivedigest.com/Whit...hite_paper.pdf

Try differing pad compositions to change the frequency profile make use the rotor are true to 0.001" and measure RA:
Major OEM's specify surface finish roughness of 100 µin (2.54 µm) or less for maximum braking performance.........profilometer is called the Arithmetic Mean Deviation of the Roughness Profile, Ra. Surface finish is measured in either micro-inches (µin) or microns (µm).
As a rule, most new OEM and quality aftermarket rotors have a finish somewhere between 30 and 60 microinches RA (roughness average) with many falling in the 40 to 50 RA range. Some say a rotor finish of 80 microinches or less is good enough for most vehicles. Others say 60 microinches is the magic number, or 50 microinches or less if the vehicle is especially sensitive to rotor finish.

 

His brakes almost sound like there metal to metal. As far as pads go, i'm not sure. He had the brakes installed before I started working on his car, the pads are the ones he recieved with the kit. He called stillen tech support again, but he's still waiting on them to call back. And that was either last friday or this past monday. Did the AP racing kit come with shims?? Cause there arent any on his pads.

 

Not having any shims is definitely one cause for the squeaks. Also need to find what pads he's using. Performance pads, especially racing pads, tend to squeak and is normal.

 

Yeah true about performance pads squeaking, but his are horrible. Stillen finally called him back. There sending him new pads and shims. They said if that doesnt fix it then theres a problem with the caliper it self.

 

If pads are not properly bed-in they will often squeal regardless of shims or anti-squeal compounds. Some pads even when well bed in will still be noisy. This is the bedding-in procedure we reccomend: http://www.stoptech.com/tech_info/wp...contents.shtml

 

The shims will work, they worked for me & its been over a year.
Good Luck