This weekend I changed my rear rotors and pads. Before the job I noticed when I spin the wheels there was a scraping noise - just at certain spots, so I assumed the rotors were warped or something. But, now with brand new rotors and pads, the noise is still there. With the caliper/pads off, there is no noise, so I am pretty sure it is the pads against the rotor. It is very minor, I can spin the wheel and it keeps spinning freely with that slight sound of it touching one or two places, but it just seems like it should not be doing that?

 

Check to see of the guide pins are frozen. More than likely thats your problem

 

I made sure to check them, they slid in and out nicely, no sticking...

 

It might be the parking brake cable still keeping some tension on the lever, causing the pads not to retract completely from the rotor. There's a service bulletin for 4th gens that covers this. You can order a new set of pad retainers for about $20. These retainers have a spring design that keeps the pads pushed away from the rotors. Once installed, the pads won't scrape the rotors when you spin the hub manually. The part number for the kit is 44083 4U025.

Will also eliminate the groaning noise from the rears when you let off the brake pedal slowly.

Here's what the new retainers look like compared to the old ones:


Here's what the look like inserted into the torque member:

 

It's perfectly normal for the pads to gently touch to rotor surface. As long as the wheel spins relatively free, you're good to go!

 

The sound will go away as they wear down. I had the same issue.

 

did you check if it was the dust shield?

 

all of this is elementary you MUST bed your brakes.. 99.9 percent of people alive who do their own wortk have no idea about this.....get wise and do it right.....google bedding

 

Yeah you should check your dust shield, I had this weird grinding sound that wouldn't go away until I got mad one day and hit the dust shield (Gently) and a little rock dropped out.

So I put the wheels back on and crossed my fingers to not hear anything and EUREKA!

 

Necro bump.

Changed out the pads on wife's i30 to some duralast semi-metallic ones. The old ones were practically gone, I was shocked we didn't start hearing it beforehand (the metal indicator broke off both pads lol).

Anyway, thanks to some tips on the frozen rotors (had to use a bolt to unfreeze them from the hubs) and how-to retract the piston (turn it clockwise with some needle-nose pliers), got the job done. Turned the rotors at O'Reilly's and slapped them on.

The installation went fine (making sure the nubs on the pads fall into the piston's nubs), but now there is a metal-on-metal scraping noise from the rears. When I turn the wheel by hand, it's definitely catching on something, but spins relatively free. Definitely not the heat-shield around the rotor.

Took it out for a drive around town (maybe 20 miles or a bit more) and the sound was still there, even after bedding the brakes (6-7 50-0 stops) Nothing smelled burned or got hot. When replacing the pads, I've also replaced all the retaining hardware and sprayed some crc stuff on the back of the pads.

Is it just the new pads that need to be broken in? I've read about the brake cables that could still be pulling on it, but from looking at it yesterday, it didn't seem like that was the case. The car rolls just fine in neutral.

Any ideas are appreciated!

 

Its your dust shield. The rotors rotate and scrape the dust shield. just bend them back some out of the way.

THe rear dust shields were so rusted they were barely holding on and scraping the insides of my rims and ripped off. They are there to keep water and dust off the rear braking systems.

 

My bad, that's what I've meant by "heat-shields" in my previous post. I'll def. check everything over again later tonight.

I think it might be the metal clip that slides inside the caliper (the one above the piston) that could be ever so slightly touching the rotor when it's spinning.

Thanks!

 

The heat or dust shields (whatever lol) may be rubbing against the inside of the rim. Mine was doing this.

The rotor should clear all bolting and apperatunces of the caliper.

 

Alright, took it apart last night and everything looks good. Seems like the pads need to wear a bit to not touch the rotors. It does look like the top of the pads are being used, not so much the bottom.

Took some pics and videos (let me know how to embed dropbox videos!).

https://dl.dropboxusercontent.com/u/...923_181230.mp4

https://dl.dropboxusercontent.com/u/...923_180540.mp4

 

Did you re-grease the guide pins?

If you've never applied brake grease to your guide pins then here is some guidance

Brakes reconditioning

The front and rear pins are greased the same.

You can get a new set of rear guide pins with their bolts and boots at autozone for $17

H15072

 

the noise seems to have gotten better. i'll keep monitoring and report back!

 

I find it baffling that those redesigned retainers is not being used when purchasing the hardware kit from Nissan. I will call and inquire about this from the dealer tomorrow.