I replaced pads and turned rotors on the front. Ever since then, after applying the brakes about 7 times, a horrendous squeal starts and doesn't go away until the brakes cool down. My mechanic has no idea why. When brakes are cold,no noise at all. BTW, these are ceramic pads. My mechanic's wife's car is a 97 850 and it does the same thing.
A good bleeding might help (or it might not.) I'm thinking if a trace of moisture has invaded the fluid - as it always does over time - when hot it would produce vapor pressure and make the fluid slightly compressible. The new pads might not tolerate that as well as the old ones did, for whatever reason.
This fix falls under the "cheap enough, couldn't hurt, might help" category.
Mike
You know...there is a whole science regarding brake squeal. Volvo instructs that the rotors on your car never be turned...and there is solid science behind that. When they're done with, they are DONE. Often, the squeal is amplified by the backing-plate which acts as a radio speaker. Often if you remove the inner brake shield and leave everything else alone, the squeal will go away permanently. The VAST majority of brake shops don't really know how to turn a rotor, much less a drum. The guys that REALLY know how to do it are making about 60k a year...and they're not working in brake shops. Cut your losses, replace the rotors and pads...or upgrade them to something really trick. Once rotors are turned by someone who really doesn't know the science, the rotors are lunched.
Squealing has nothing to do with the fluid. If it did, the brakes would have been squealing before hand.
Remove the pads and put some (orange colored liquid) Disc Brake Quiet on the rear of the pads and on the pins.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.