So its my girlfriend who owns a rx-8. 2007 w/60K miles. Plaza Tire and her family mechanic says the reason why her brakes sqeak after a rain is that the water has caused a rust build-up (this is overnight mind you) and the next few times shes drives it, when slowin down or stoppin, her brake noise kicks in. I know nothin about Mazdas...any insight? Thank ya much.

 

Rust will build up overnight (look at the rotor and you can't miss it), and it will grind off as you use the brakes making a bit of noise as it does so, but I would only expect it to do so for a short while. For example, I woke to rain this morning, my rotors were speckled with bright orange rust. Within minutes of driving and using the slightly noisy brakes the rust had rubbed off and the brakes returned to normal.

If this describes her experience, then there ya go. If her condition persists longer or involves much more noise, then maybe it ought to be reevaluated.

 

Metallic pads

 

fact: RX-8 brakes can squeak sometimes for various reasons. It's not a problem unless you make it one in your (her) own mind. So...choices...1) waste time, money and aggravation trying to stop what is a known, normal occurence with these brakes, or 2) get over it and get on with your (your gf's) life (recommended ) That is all.

 

Hey thanks ya'll for the replies. I'll pass the info on to'er. Sure she wont care for it too much but hey...its her car and money is spent elsewhere than doin this-n-that to it. Thanks again.

 

It's not the rust on the rotors after the rain, it's the rust on the back of the brake pad backing plate where it contacts the caliper piston. That's where you lube with brake grease to keep pads quiet. If it's been awhile since the brakes were serviced the grease gets washed off and rain causes rust which makes noise when the backing plate vibrates against the caliper piston. Grease em or get used to the noise.

 

If you use the Ceramic Extreme (on the left)...it will resist melting off ...washing off ... or degrade with temp/salt/water/etc....as the bottle says. You can usually buy small single application sizes at an autopart store.

 

I have the same problem. From reading other posts here, I figured I would have to live with it. I found tubes of the Ceramic Permatex lubricant locally for $2 a tube (one tube per axle recommended). Hard to believe I've been putting up with this squealing and it'll only be $4 (plus tax) to fix. I'm not too experienced working on brakes, so does anyone have pictures that show where to put the lube? I have the service manual in *.pdf form, but it doesn't mention this particular fix. And I don't want to mess up my brakes, I enjoy this car too much to have anything nasty happen to it.

 

^ look at your .pdf under brakes. Where they indicate "anti-rattle brake grease" use that stuff instead. You don't want to put a lot on, just enough so you can spread a **thin** as in thin coat on the pad backs, did I mention a thin coat only? put it on the the various shim pieces as well and then a VERY small amount (match head size) on the sliding clips for the pads where the pads rest against the clips (these are called the "Guide plate" in the .pdf and there are 4 per caliper).

As for putting to much on the shims and pad backs, if you do end up putting too much on there, it will be compressed and oooze out (mess) when you apply the brakes and you'll need to clean it up (messy and a PITA) as it's definitely not something you want on your rotors or pad's surface contacting the rotors.