starfishy

On my '00 SS I have this loud 'clattering' noise, which appears to come from the front left under heavy braking. Actually it sounds more like dragging something metallic across the asphalt on a string, but i cant see anything hanging down in either the wheel house or elsewhere under the car. I took off the wheel and checked the brake, but the brake rotor appears to be fine and the pads have plenty of material left, The air dam is not hanging down either.

Thinking it may be the catalytic converter, as I had read, I removed it, but it does not seem to have anything loose inside and I reinstalled it.

Any ideas what else I could check?

biketopia

iTrader: (5)

Pull your wheel again and look very closely at the backing plate behind the rotor. look for shiny spots where the rotor is hitting. Check the suspension bushings, a worn out one can do some wacky things under a hard slow down. Check the right side too, being in the driver seat can make you thing a noise is coming from somewhere they aren't, chased my tale for a while with noises only to go for a ride with a co-worker and hear it's 5 times louder in the passenger seat.

chrysler kid

iTrader: (14)

My wheel bearing went out and caused a screech like the brake pads. It eventually got bad enough to cook the abs sensor and trigger the abs code

Pull the caliper and the rotor and try to rotate the hub on its own. It should feel firm and spin smoothly. If it feels like it spins fine but feels a little gritty as it spins then it is bad

biketopia

iTrader: (5)

another good wheel bearing check is to jack the car up, with the tire on, grab it at 12 and 6 o clock and see if it rocks back & fourth, it shouldn't move at all.

starfishy

Thanks everyone!

I checked the wheel for play when I had it on the floor jack. It feels rock solid.

The noise now almost reminds me of this plastic wrapping GM puts around the cables (the black ribbed stuff) rubbing on something spinning. Just now I checked whether there was any of the wires in the engine compartment that could get close to the serpentine belt, but everything looks in place and fixed.

I'll try to take a video.

starfishy

Here is the video:
It seems to come from the very front. that it continues for seconds after the car is stopped makes me think that it is not directly related to the brakes or wheel bearings. took the serpentine belt off, but the noise persisted.

chrysler kid

iTrader: (14)

I've never heard a sound like that come from a car.

Uh if I had to guess it sounds like gravel in the oil pan sloshing forward under braking

starfishy

I had never heard this sound either. I think, though, that if there was gravel in the oil pan the engine would not be running normally, would it?

chrysler kid

iTrader: (14)

No clue

You said it makes this noise even without the belt being on, the only other conclusion I can think of would be the abs module

starfishy

That's a possibility, but I don't think that's something I can do myself. I found a broken horseshoe clip on the ABS cable on the passenger side earlier, but fixing that didn't make the noise go away.

Otherwise nothing is loose in the wheel wells, the wheels spin freely, the brake pads have about 50% life left, no play in the wheel bearings or ball joints.
I didn't see anything hang down, the air dam is mounted properly and all the bolts of the cover underneath the bumper are in. Still, it sounds like dragging mesh fence on the pavement.

biketopia

iTrader: (5)

That's exactly what my co-worker said when I played the video. To isolate the ABS possibility pull the fuse or unplug the controller so it can't activate and see if it still makes the noise. Does your pedal feel funny?

starfishy

Brake pedal feels normal, no pulsating, smooth deceleration. I'll pull the ABS fuse tonight anyway to eliminate this possible cause. I also checked the underside of the car again for anything hanging down, but nothing. Wheels are properly torqued and rotate freely when the car is on jackstands.

bleepster

iTrader: (2)

sounds like a rock tumbler - man - doesn't sound good at all. I'm sure you were not serious, but its NOT gravel in the engine - or else it would "slosh" back upon acceleration.

subscribing - cuz i want to know the cure

pulling the ABS fuse is a good idea

does it do it in reverse?

have you checked transmission fluid for discoloration or anything? just throwing out ideas

starfishy

I haven't tried braking hard in reverse, but I backed up a few hundered feet several times to run tests and not once had this noise during backup. Will check transmission fluid tonight. Shifts are smooth, clutch engages and disengages smoothly.

FirstYrLS1Z

iTrader: (4)

Muffler guts loose ?

ghardester

The noise continues even after the rotation of the wheels has stopped, so I don't think it is related to the brakes or wheel bearings. Or even anything related to the front wheel rotation.

Is something in the engine compartment shifting forward to hit the serpentine belt or pulleys only when you are stopping but isn't rubbing when you look under the hood at idle?

The other thing that happens when braking is that you have the clutch in. Any noises at any other time while shifting? Is there a loose nut or rock rattling around in the bell housing that only makes contact while forward braking?

That is damn weird! But since the noise continues after the wheels stop spinning I would look at causes other than the wheels/brakes. Have you taken a good look at the drive line? Got a wire or something wrapped under there? Just ideas to look at.

biketopia

iTrader: (5)

Loose heat shields, motor or trans mount flexing and letting something hit the serp set up maybe? I'm kind of at a loss. Is there an inspection plate on the m6 cars? A buddy has a wrx i did a clutch on a year a go and when we took it apart a pressure plate fork and spring had broke, never any weird vibrations or issues driving, it made a noise when he first herd it fail, but maybe you've got something that isn't falling out? Just throwing ideas out now.

starfishy

@FirstYrLS1Z I havent looked at the muffler yet, as it is in the rear and I thought the sound was coming from the front, but its possible, I'll check that tonight.

@ghardester I had the serpentine belt off without change. Checked for anything loose in there, but couldn't find anything. The accessories likely are not to blame as without the serpentine belt there was no change to the noise. Only thing I havent detached yet is the AC compressor. Noise is present with and without the AC on. No noises while shifting, nut in bellhousing is a possibility, but that would probably be felt in the shifter when the noise happens and I didnt feel anything. I did a visual check of the driveline, didnt see anything. Will recheck.

@biketopia I checked the drivers side heat shields. Will work on the passenger side tonight. The noise is there without the serp, so anything hitting that is probably not the issue, unless the driveshaft pulley itself hits something. Need to see how i can check the motor mounts without a lift.

starfishy

Thought I fixed it, extracted a 1/8" pebble from under the drivers side exhaust heat shield. After that I made a good half dozen stops and couldnt reproduce it. Until I got back from dinner with the car, noise is back.

I also found the forward exhaust hanger (exhaust is SLP dual-dual) on the passenger side worn to the metal. I reversed the rubber piece, but that didnt help either. The piece is discontinued, alas, so I will have to find some solution.

So back to square one. Tomorrow I'll check all the heat shields, maybe there are more pebbles where this one came from. Passenger side cat. I felt some vibration on the last test to the right side of the drivers side foot well, while my wife thinks she felt something on the passenger side. Not sure what to make of that. Clutch? But then would the car shift fine and the clutch engage and disengage smoothly?

bleepster

iTrader: (2)

I am no expert, but I beleive it is something internal. I think transmission. The noise sounds like rock or bolts spinning in a coffee can. Its not brake related, wheel related, as the noise continues after the car stops.

its not exhaust.

maybe look in the tranny bell housing. maybe there is something in there.

could the guts of the torque converter be bad? maybe due to cyntryphical force while driving, you dont hear it, but once you slow down, the loose bits start to fall?

again, i am no expert, just offering you what I would check out.

did you pull the ABS fuse? ABS modules can make some pretty weird noises at time.

vibrations to the right of the foot well, that is the area of the transmission.