Scraping noise problem. Help please

86_Chaser
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Scraping noise problem. Help please

Postby 86_Chaser » Mon Apr 01, 2013 11:32 pm

i have this scraping metal skipping sound coming from my rear end. i notice it more from rear right side. you can ONLY hear it super clearly when the rear seats are down. when seats are up, you barely notice it. Not sure if its normal because I'm running a lsd with 4.7 pinion gear. Also I lift it up on a hoist, couldn't heard from the outside, maybe due to my exhaust :) but you can kind still heard it inside.

-TRD 4.7 pinion gear with Kaaz 2.0 way LSD (supposedly the rear end was rebuilt)
-fresh motul 90PA oil
- greddy coilover, max out in the rear
- rebuild rear caliper with oem rebuilt kit and stainless brake line
- pepboys rotors with portfield pads with 3,000 miles on it

not sure if this could be the cause of it but before i change all pads and rotors. it made this very deep groan noise when reversing out but once its rolling it goes away. but sometimes it will come back during light braking. you will notice it more in the morning or when the car sit for a long time. it had project U pads on it. after changing all pads and rotors. i thought it was my rear calipers getting stuck/sticky or something. So I rebuilt the rear calipers. the groaning noise kind went away but its comes and goes. its better then before. im guesssing because im running racing pads. racing pads are hard material and its touching a cold surface rotors which creating the groaning sound???? Or maybe defective pads??? But once the rotors and pads are hot, it goes away.

but im not too worry about the brake groaning noise. unless it part of the scraping metal skipping sound.

help please.

ga_goosh
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Re: Scraping noise problem. Help please

Postby ga_goosh » Wed Apr 03, 2013 10:59 am

check your center support bearing on your drive shaft. you should also check your rear wheel bearings too.

the groaning sound from your brakes is normal for semi metallic pads. they are also known to brake better after warm
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86_Chaser
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Re: Scraping noise problem. Help please

Postby 86_Chaser » Wed Apr 03, 2013 5:08 pm

ga_goosh wrote:check your center support bearing on your drive shaft. you should also check your rear wheel bearings too.

the groaning sound from your brakes is normal for semi metallic pads. they are also known to brake better after warm


I thought bearings makes a deep groaning sounds when they are about to go bad and not a skipping metal sound. How do you check for a bad drive shift bearing?? When I lift the rear end up and spin the wheel by hand, I didn't hear anything weird beside the pads touching the rotor sound. Is there a to test if the wheel bearings are bad beside taking it all apart??

That's what I thought. Thanks

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Re: Scraping noise problem. Help please

Postby KonaTrueno723 » Wed Apr 03, 2013 11:02 pm

Vibration will be the issue if it's your DS.. & you can tell if it's your rear wheel bearings,,it will have a noticable howl & then radiate into the car. Pull the rear brake pads off & see what they look like..maybe they're not wearing in right to the rotors?
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86_Chaser
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Re: Scraping noise problem. Help please

Postby 86_Chaser » Sat Apr 06, 2013 10:46 pm

KonaTrueno723 wrote:Vibration will be the issue if it's your DS.. & you can tell if it's your rear wheel bearings,,it will have a noticable howl & then radiate into the car. Pull the rear brake pads off & see what they look like..maybe they're not wearing in right to the rotors?


There's no vibration at all. So I'm guessing my DS is okay. Doesn't sound like any howl or radiate sound. More of a skipping sound. If I pull my e-brake up while driving, the noise is still there so I don't think it's my pads/rotors that are making that sound. But it does sound like it. I will check the pads again and see what's up.

I lifted up the car on a hoist to see if you can heard from the outside/ underneath. And my friend told me that he didn't heard anything beside my loud exhaust. He did mention that my tranny was loud/noisy. So I flush it out and put new fluid. Hoping that will fix the problem but it didn't. The only thing I can think of is my pinion gear/lsd that is making that noise or its normal and never notice it till now.