Hey folks, how's everybody?

For a good 10 years now I've been driving my 2002 XL-7 and put on almost 160,000 miles on it, have babied the living hell out of her, try to use the best parts money can buy when needed and so on.

But for the last year or so I have changed my front pads and rotors THREE times because I keep getting this ultra annoying god damn squeal as I come to a stop or apply light pressure to the brakes (when creeping idly by like waiting in a drive through or slowing down for what having you).  I have exhausted ALL possible source of noise and its beginning to make me insane!!

I have made sure of the following:

- pads are properly installed and have applied a plentiful coat of tacky anti brake squeal material to the non-friction side of the pads
- also removed the shims, applied the same material on their back sides and reinstalled the shims back on the pads
- have tried REMOVING the shims, and just having the pad alone with the anti-noise paste on them
- made sure the anti-rattle clips are all NEW and in proper position and have brake lube applied all over them as they sit in the cradle
- grinded off the paint off sides of the pads so it doesn't have a chance to curl up upon itself and make possible noise
- made sure the hubs are cleaned
- replaced the calipers TWICE and made sure the sliders or pins are all clean and lubed and properly bled
- replaced the brakes hoses

Ive used different name brand pads and rotors, cant remember what the first set was, but then I tried WBR and they were THE WORST.  I then I tried AC Delco's front coated rotors and all cermaic pads and everything was dandy for about a month but as this morning its come back but not as loud as before.

Heat is a definite factor, back in the summer with the WBRs they were squealing like friggin CRAZY the second the brakes warmed up.  It was ultra annoying and embarrassing.

Again its only at a certain pressure, if I let go it stops, if I press harder it stops but at that sweet spot which is what I use the most for coming to a reasonably and comfortable stop it goes nuts!

What am I missing here??  There is no sign that the rattle clips are rubbing on the rotors.  There is no sign of any contact amongst parts that shouldn't contact (just the pads and the rotors as they should be!).

The only explanation I can come up with is that as they reach a certain temperature, the material in the pads and the rotors just don't mix and this is what happens?

I wanna try organic pads but cant seem to find any.  Semi Metallics for sure are painfully loud.

I can live with small squeaks here and there and the odd squeal every now and again but this is getting ridiculous and Im getting insanely frustrated!!

Any insight is very much appreciated.

I can't help with the squeal, you seem to have tried every thing I would have suggested, and a few I hadn't thought of, but if you want to give organic pads a shot try EBC Greenstuff (DP61099 - available on Amazon) - I have not used these personally, although I have purchased them, I have not yet gotten around to installing them - it's probably going to happen early in the new year.

Thanks for the tip.  Upon closer inspection it looks like they are over heating...  It doesnt add up.  My driving habits have not changed yet the noise presents itself every time.  I've blown almost $500 on trying to fix this problem.

If you have signs of the pads/rotors overheating, they may be dragging - you've already replaced calipers and lubed the slides, ruling those out, but other possibilities would be hose(s) being partially blocked (they act as a one way valve), master cylinder not returning fully when released, or the pedal/booster free play being out of whack - this last is very unlikely unless someone has tampered with it - it's a set & forget deal.

Alright its been over half a year and I believe I have found the problem.  Its the ceramic brake pads.  It was the common clue when I reviewed each and every installation.  The ceramic gives off a harmonic that is a by product of the heat and shape of this brake system.

I switched to Semi Metallic pads and the noise has not happened since installation back in January.  After switching rotors, calipers, hoses, fluid, shims and lubes, this is what I firmly believe fixed my issue.

I noticed on other forum with various other makes and models people suffering from the same symptoms.  If so I suggest try semi-metallic pads.

Finally, what a relief.

Thanks for posting up the solution! My XL7 makes an annoying squeal on light braking applications, like you described, although maybe not quite as bad because I've learned to live with it because my cheap self won't change the pads out until they're good and ready to be changed out! Haha!