StopTech Rotors rubbing
 

Installed my Stoptech rear slotted/drilled rear rotors yesterday. there is an intermittent scrapping/rubbing sound coming from the left side. I can especially hear it when driving with the window down and close to the center island or in an alley.
Is it because the pads need to wear to the new rotor, I have 8300 miles on the old ones, or is it possible the rotor is warped or bent?? the right side does it slightly but not nearly as bad. When I installed the fronts I never had this issue, there was only about 3000 miles on the car though. Any thoughts, suggestions appreciated :tup:

Yes, it usually takes a while for the pads to seat to the new rotors. The noise you hear is excess grooves in your pads being worn off by the new rotors , as they aren't fully seated. No need for worries.

did you follow their recommended bed in procedures?

StopTech : Balanced Brake Upgrades

You have to drive for 20 or 30 miles to wear off the coating before following the bed in procedure.

The extra noise could be from the drilled rotors (which I don't recommend to anyone) or it could be from high spots on the pads if your old rotors weren't perfectly flat.

I wasn't sure about that process, because the pads were not new, but I see now that they still recommend it. I will give it a try :tup:

Well, I driven about 50 miles now, so I will try it. thanks :tup:

good luck, let us know if it helps

Ok, did the bedding in procedure, have about 100+ miles on them so far and still have the scrapping sound. If it's high spots on the pads, how long before they start to seat on the rotors?? Or should I just replace the pads? there is about 8300 miles on these ones, they are the stock pads.

couldn't hurt to try a different set of pads... always helpful to have an extra set anyways... give it a shot... try another brand and compound as well

Yeah, driving home to night, the lite scrapping sound has now turned into a chirp.
chirp, chirp, chirp, chirp, chirp, I think I have a hamster wheel or birds in my brakes :rofl2:

Ok, seriously, I'm a bit concerned because I'm taking an 800+ miles trip on Friday.
So, I either try new pads or put the stock rotors back on, or hope that the pads seat to the rotor during the trip. What are the chances that the rotor surface is not machined correctly?

Also, if I change out the pads in the rear, should I change the front too? or is it ok to run different brands front and rear?

ok to run different brands IMO... and i'd guess 90% likely this will work itself out... remind us, which pads are you running ? OEM pads ? were they new at time of install of rotors ?

Ok, cool, I was thinking of trying the Hawks, any recommendations?
Pretty much street use with an occasional canyon run once a month.

Yes, I have OEM pads on now, there was about 8300 miles on them when I installed the rear rotors.

my recommendation is OEM recommended pads unless you plan to track it... this may be unpopular with some ppl, but until you start having fade issues, no reason to upgrade the pads... and some of the higher friction pads have downside too, like more dust, longer to build up heat and perform, etc

If the bedding in procedure didn't help matters, you may have some debris between the pads and rotors. Perhaps a rock or something of the like.

Did you follow my installation procedure? It almost sounds like your rotor isn't perfectly flat against the hub.

they are floating if im not mistaken, meaning they are tighened by the wheel nuts. i assume if his wheel is on, the rotor is on ok.

Besides that, if they weren't on correctly, there'd be a lot of feedback through the steering wheel.

Not necessarily. Yes, they are floating but caliper is not floating (in the sport package). So you could have slight rotor run-out from rust on the hub and not necessarily feel it under braking as much as you would with a floating caliper.

Is possible that when they installed the rotors. The brakeline wasn't
Properly bled so now when the brake is relased the trapped air in the line has
Not allowed the brakes to re open properly?
Jus a thought?

If that was the case, then there'd have to be a leak somewhere. AFAIK, air can't "form" inside a brake line or caliper unless something allows it.

Granted, over time, the pistons will let microscopic amounts of air through, or, if you boild the brake fluid it could get gasses built up, but considering he changed the rotors and it started happening...maybe it's a defective rotor? (crazier things can happen!)

Put the old ones back on, and see if the problem persists?

fitment issue?

There are several likely candidates for the scraping sound:

1. Your parking brake shoes are not centered and are rubbing on the inside of your rear rotors. (The 370Z uses a "drum-in-hat" parking brake design, where the rear rotors double as parking brake drums.)

2. Something is not right with the pads or the installation of them.

3. When you installed the rotors, you inadvertently bent the rotor dust shield, so it's scraping against the inboard side of the new rotors.

You can test these theories. The next time you start hearing the scraping sound, gently pull the parking brake lever to see if that changes or eliminates the sound. (Do this carefully and with your finger on the button, so you can release the parking brake quickly.) If it has no effect at all, then theory 1 is dis-proven.

Next, gently depress the brake pedal. If the sound stops when the brakes are applied, then reappears when they are released, there's something going on with the brake pads. Pulll them out and inspect for anything unusual. Like, did you install one backwards? (No insult intended - this is more common than you think!)

To see if it's the dust shield, you'll want to put the car up on a lift or jackstands and pull the left rear wheel. Then use a flashlight to see if you can see how much of a gap there is between the rotor and the dust shield. If it's really tight, use a couple of large screwdrivers or small pry bars to bend it back a little, making sure you're not simply moving the problem from one part of the dust shield to another.

Hope this helps!

I though the parking brake only engages the rear brakes?

+1, I just changed the brakes on my Civic a couple weekends ago, it scraped and "rubs" and makes all kinds of noise - until they get mated up...

They don't make as much in the way of wierd noise now. I imagine with anything more than standard-issue semi-metallic's and plain/smooth new rotors, the noice would be even more-so.

That is correct, and that's where he is having his problems.

On another note, glad you found the forum Dave! I wound up ordering those brembos I was discussing with you through my wholesale account at tire rack.

A guy on the M45 forums complained of the same noises, turns out the 4 bolts that hold in the hub bearing to the spindle actually were backing out and 2 were completely backed out. this was letting the hub wiggle where the spindle was stationary causing the scraping noise. Not sure what caused it but it's worth it to check yours.

Oh, btw - The 2006 Infiniti M45 shares the same hubs as the 370z

Thanks for the advice :tup: I have checked all these points, and that wasn't it. It seams to pretty much have disappeared now, I've got about 3000 miles on them since the install, the only time I can hear it is when lightly applying the brakes, but as soon as more pressure is applied, it goes away. When they were first installed the one side would make the noise just driving or coasting. I think there was/is a high spot on the pad or rotor that has now worn down. I've just learned to live with it. :-)

thx for updating us

Exactly my thoughts..

This can be true as well, but it is unlikely. You would have wheel vibration as well.