rear disk brake noise

So there is a noise that comes from the passenger rear side on my 85 nissan 300zx. It does not sound like metal. Metal makes a grinding like noise. This sounds almost like if you have your bike upside down and pedal it and push a stick against it or something else. Its more of a rubbing noise. I have felt around but there is nothing making contact with the tire itself. The brake pads have 80% life left. It is disk brakes in the back. I only hear it at random times. It seems to be after driving for a few minutes and it comes and goes. It is a little louder when I turn and when I push the brake it will actually stop. Any thoughts?

Are you positive it is coming from the passenger rear? Have you taken the wheel off with the car safely supported and inspected the braking system, making sure the dust shield is not near the rotor? Is the parking brake built in to the rear caliper or a separate drum system within the rotor? Is there a ridge of rust on the rotor friction surface (inside or outside) that is polished from the brake pads rubbing on it?

-Rod

Are you positive it is coming from the passenger rear? Have you taken the wheel off with the car safely supported and inspected the braking system, making sure the dust shield is not near the rotor? Is the parking brake built in to the rear caliper or a separate drum system within the rotor? Is there a ridge of rust on the rotor friction surface (inside or outside) that is polished from the brake pads rubbing on it?

-Rod

I didn't take the brakes off. I think I may need to see the back side of the rotor cause the front doesn't have any grooves. The emergency brake I would have to say is seperate. I mean it is connected just underneath the entire system and just behind the rotor itself. I don't think its rubbing anything. Ill get the brakes off on that side and look at the rotor from the back since there isn't enough room to view it without doing so. I THINK it is the rear passenger side.

The Z31's parking brake is built into the caliper.

Check that the calipers are sliding freely on the mounting bolts. If they stick, then one of the pads remains in contact with the disc and wears it out sooner than the opposing pad.

The other possibility is that the caliper is leaking and contaminating the pad.

Good luck!

Most likely, it could be the build up of rust and also the person who put them in. if you don't put them in correctly it will make a lot of noise in the future..not good, but in the future i think you should buy (Wagner's Thermal Quiets rotors/brakes or ceramics) very good investment! :cool: