I recently started to hear a weird noise coming from the rear of my car. That day the car was washed so I did not think much of it at first. It sounded like that sound you hear when the brakes rust against the brake disc and you hear that scrapping noise as the pads go past the rust point. When I heard it I applied the brakes and gas to try and clean the discs. The noise didn't go away. It mostly sounds like a scraping or grinding noise from either the left rear or center rear. I cannot tell exactly. The noise remains when coasting in neutral. It seems to happen on the exact same spot of the revolution of the rear tire. If I go faster the noise frequency increases and if I go slower the frequency decreases. I jacked up the car and tried to shake the rear wheel to check the bearing and it seemed fine. I inspected the brake area to see if something was stuck between the shield and the disc and could not find anything. I lowered the car and drove again and the noise wasn't there. Then it happened again tonight. It seems that when I apply power the noise goes away or gets less. I am not sure if that is due to the noise of the engine or the torque to the rear is getting rear of it. If I am cruising at a steady throttle I can hear the noise. If I coast in neutral I hear the noise. The noise also seems related to the temperature of the car? I just took the car around the block and I heard no noise. When I first hear it I remember not hearing it at the start of the trip but when I got off the freeway I could hear it. Can anyone help me figure out what the noise is coming from?

Summary:
- 2001 S2000 with 55k miles. All normal scheduled maintenance have been performed at local Honda dealer.
- Noise is linked to the revolution of the rear and happens at the same spot (assumption) in the revolution of the rear tire or axle.
- Noise is a scraping or grinding type sound.
- Noise is coming from left rear or center rear.
- Heavy throttle seems to make it diminish.
- The noise is easiest to hear when coasting very slowly in neutral.
- The noise occurs regardless if the brake is applied or not.
- The noise comes and goes between drives of the car. When I hear it I usually hear it for the rest of the drive. The next day it may be gone.
- The noise may be related to the temperature of the car or length of drive?

Thanks in advance for any help provided!!!

- John

 

Does the tone of the noise vary in any way when you lightly tap the brakes while cruising on neutral? If so, I'd check the pads, specially if they haven't been replaced in a long time.

 

Re: CapoAregentio - Yeah I thought that it might be pads but the sound doesn't change with relation to how much or little pressure I apply with the brakes. I had jacked up the car and removed the wheel to inspect for a twig stuck in the brake area and when I looked the pads were fine. I did not spend a ton of time inspecting the pads so I will go back and double check them to make sure they are not low. I believe they looked like they had 60% left.

 

I see. I'd personally change the pads anyway. They may have 60% left but they might be crystallized. I am confident that doing this will fix this issue and if not, it wont hurt because at least you'll have fresh new pads in there. If you go this route, dont forget to get the rotors turned if needed.

Too bad your not local. I'd take a look at your S2 free of charge

 

It's the wheel bearing, I had the exact same symptoms as you.

In the DIY/FAQ there's a thread on how to replace it. The easy cheap way as I did is to get the complete knuckle assembly on ebay or someone locally that has a used part, then just swap the whole assembly. If not you'll have to buy a new one and have a machine shop press the new bearing in.

 

If you are hearing the scraping noise then you will most likely need to replace the knuckle as well as the bearing. I just went through this on my pass. side. An easy way to verify this is to touch the hubs after a decent drive... a bad wheel bearing will generate more heat than normal. Also, mine went from a squeak to a loud grinding noise in a few thousand miles and although it was indeed coming from the right rear.. it sounded very central from the driver's seat. (I thought it was my diff at first)