Greetings and thanks for your time!

I've got a 2004 Si that has a really loud metal-on-metal sliding/grinding sound coming from the front wheels. It doesn't seem like it's the wear indicator on the pads because sometimes it will make the noise when I'm not even pressing the brake. I know it's in the brake pad/rotor area, though, because if it does it while i'm not braking, I can pump the brake and the sound will stop upon releasing the pedal. I've got it in the budget to replace all pads and rotors (if machining isn't an option) but just wanted to get a second opinion and see if that seems like it would take care of the issue.

Thanks again and let me know if anyone needs any additional information.

 

the problem is worn out brakes and or something stuck between the pad and the rotor. take them off inspect.

 

Also could be wheel bearing on the way out. Thats what mine did for a week or 2 before it started squeaking all the time.

 

crap... is a wheel bearing the same as a CV, or the inside of it? (sorry - more of an interior-ist).

It just seems like it'd be brake-related since I can control the squeak with the brake pedal... I'll look into both, though. Thanks

 

Nope. The wheel bearing is part of the wheel hub. The CV is the constant-velocity joint, which allows the axles to turn while at an angle without binding.

If it's a grinding noise, it could very well be a worn wheel bearing. When it gets bad enough, it'll eventually sound like an airplane. Actually, by that time you'll probably be able to feel the vibration from it in your seat.

Is it more noticeable when you turn one direction than the other (at a decent speed. Like 30mph+)?

 

reaper -

actually, the faster I travel, the less it happens. once I hit about 45 it completely goes away until I brake. at lower speeds, its more noticeable on the right side when I turn left but is still pretty constant when driving straight. i'm just wondering if somehow the brake pads are laying against the rotor and not retracting and the higher speeds provide a greater "air cushion" to hold the pads off the rotor. also, at lower speeds it will go away if I play with the brake enough but if i hit a bump it comes back.

I hate to sound like i'm just trying to counter everything you say but just want to make sure i'm getting all the info on the table.

Thanks a LOT for your help.

also - dont know if it helps but i'm at about 87,000 mi.

 

No problem, we're here to help. Right now, I'm just trying to eliminate things it could be. If it's noticeable at low speeds but goes away at high speeds, I think we've eliminated a wheel bearing as the cause.

When's the last time the the brakes were changed? (pads and rotors)

Also, does it pull at all when you brake hard?

 

reaper-

no pulling at hard braking (that I've noticed, anyway). I'll keep an eye out tomorrow.

to my knowledge, the rotors have never been changed. I bought it with 14K miles and haven't changed them myself. And I know the pads are shot because the last time they were changed i didn't have the rotors machined and put some pretty bottom-of-the-line pads on it (financial constraints at the time).

Thanks

 

I would probably take a look at the pads to see how they're wearing. If they're worn down, I'd say replace the pads, turn the rotors (if they can be turned and remain within spec), and while the pads are off and the caliper is unbolted, check the sliders on the calipers. They should be easy to pull out, and they should retract by themselves. If you push them in, they should pull themselves back out of their cylinders a little bit. If it's not pulling, I wouldn't think it's a sticking caliper, but who knows?

What's throwing me off is that from the way you're explaining it, it seems like it's an intermittent problem. The fact that it makes the noise even when you aren't braking doesn't help narrow things down, either lol. I feel like I'm overlooking something ridiculously simple lol

 

reaper-

i did inspect the sliders about a month ago (when the problem first started creeping in) and the sliders returned freely to their resting position after being pushed and pulled so hopefully that's still the case.

I think i'll go ahead and start with the pads. just wanted to make sure that the problem wasn't somewhere in the caliper that would create the same issue later on so thanks for the insight. much appreciated.

I'll see if i can get to it tomorrow. a bit nervous about removing the bolts that hold the rotors to the hub (heard some horror stories about them breaking... is WD-40 sufficient to loosen these?) but we'll see what happens.

Thanks and hopefully I'll have an update tomorrow.