Rattle/grind while decelerating...?

[COstyle]

Im getting a funky grinding rattly noise when I am decelerating. It kind of sounds like a loud brake or something but Im pretty sure its transmission related. If I engage the clutch, the noise will go away. Its possible that it makes the noise under acceleration too but I cant hear it over the exhaust/engine. About 1000 miles ago I put in a fidanza flywheel and spec stage 3 clutch. Im kind of afraid its related to the flywheel but would like to avoid dropping the tranny if not nessisary. Any ideas? Thanks...

[philbro]

i know it sounds simple, but does this happen when you let off the gas, or after you apply the brakes? I had a similar noise, it was my rear calipers, the seals where all messed up an dirty and the piston would not do back so they just ground my rear pads down to nothing. From what i hear this a common probel, and a lot easier to check out than pulling your tranny off.

[COstyle]

Hmm I guess thats something to consider. However I am pretty sure the noise goes away all together when I press in the clutch. At this point ill entertain any ideas...

[doainwpg]

i had a similar noise & it was my carier bearing

[MrSpArkle]

The condition under which my rattling/grinding noise took place was as follows:
Cruising on highway at stable speed, i let off the accelerator while in gear(no brake), and then as the car starts slowing down, horrible rattling/grinding ensued.
until i pressed down on the clutch pedal.

If this is happening to you, you probably need to change your throw out bearing. when i took mine out it sounded like a baby rattle and had a alot of play.

[transient]

The throwout bearing should only give you a lot of noise when it's actually in use, ie, when you have the clutch pedal depressed, not the other way around. I had a problem where if I put my car in neutral and let it idle, I had a nasty grinding / scraping coming from the tranny. It got messed up after I had my gear oil changed as far as I can tell, and it killed something on the input shaft.

I'm not saying this is your trouble, but if it's happening when you aren't touching the clutch, then I would really doubt that it's a problem with the throwout bearing.

[COstyle]

I wouldn't have thought it was the throwout bearing since I replaced it about 1000 miles ago with the clutch and flywheel but at this point thats what Im leaning towards...

[sil_8t]

its defianty a bearing

[Flybert]

When you replaced your clutch, did you disassemble the driveshaft at the large rubber bushing? If so, you fucked up the driveshaft balance and that is what is causing the vibration. It's a vibration that only happens in gear when decelerating from 2500-2000 right? I have the same problem and it's because I disassembled the driveshaft. Or, did you put the driveshaft in the same rotation on the diff as before? It could be that as well.

[andrave]

my car does that, its rattling that comes from the clutch area... but that motor isn't gonna be in much longer so I just don't leave it in gear with the clutch in as a I coast to a stop.
least I know what it is now tho.

[ZenkiSilvia]

Flybert - you're last post to this thread is EXACTLY what has just started happening to my car. I had a shop install SPec Stage 2 with Findanza Flywheel. It's making the exact noise that was described above at the exact same RPM's you mentioned (2500-2000) on decel ONLY.

Would the solution to this be to REBALANCE/Re-Align the Driveshaft or replace the Carrier Bearing? I'm assuming it could be any of the two/combination of both. Just curious as to what worked for you to try and aim for that first and get it fixed right away. Thanks.

PS - this just proves that the search button works for almost ANYTHING!!

Booyakasha!

-Zeki

[Flybert]

We had a long discussion on Freshalloy about the problem I described. We all talked about the upgrades we had etc. It turned out not to be the driveshaft. It's actually the spring design in 6 puck clutches. They are not properly balanced to cancel out harmonic vibration when the car is decelerating from 2500-2000. The only way to fix the problem is to get an organic disk clutch. A guy with the screen name Def on freshalloy figured it out and decided to use an organic disk clutch and it worked right away.

I've read that the exedy 3 puck does not have this problem. I don't think super singles have this problem either so you might want to consider those in the future. I know I am. O yeah, the whole 6 puck problem is the same on SR and KA. I know because I had both and the problem remained the same because I used a 6 puck for both.

[ZenkiSilvia]

Despite having a Spec Stage 2 which is not pucked in a sense, it does resemble the Centerforce Dual Friction but has more solid of a disc. It is certainly NOT a "6 Puck" clutch. Regardless, is this noise damaging to the car in ANY way? or just one of those things this i'm gonna have to get used to? Thanks.

-Zeki

[Flybert]

Just checked out the pics of the spec stage 2. The material is much harder and doesn't allow vibrations to dampen as well as an organic. I bet the material is the same as many 6 pucks.

The only problem that I've noticed from this vibration problem is that my differential seal started leaking gear oil after a year or two of daily driving. I'm 99% sure this was caused by the vibration in the driveshaft created by the clutch. Nowadays I only drive my car to the track and back about once a month so I do not know of any other long term effects caused by daily driving it.

And yes, I'm 100% sure this problem is caused by the clutch disk you are using.

[ZenkiSilvia]

Well not that it's good news but it's great to figure it out. Thanks again for your help Flybert. This thread has been awesome. Thanks everyone who contributed to this. Have a good one.

-Zeki

[EchoOfSilence]

Originally Posted by Flybert

Just checked out the pics of the spec stage 2. The material is much harder and doesn't allow vibrations to dampen as well as an organic. I bet the material is the same as many 6 pucks.

The only problem that I've noticed from this vibration problem is that my differential seal started leaking gear oil after a year or two of daily driving. I'm 99% sure this was caused by the vibration in the driveshaft created by the clutch. Nowadays I only drive my car to the track and back about once a month so I do not know of any other long term effects caused by daily driving it.

And yes, I'm 100% sure this problem is caused by the clutch disk you are using.

I'm using an organic clutch with a heavy duty pressure plate and i still get this noise. I had this noise before i put the clutch in, and it was running on a slipping OE clutch. For some reason i don't think it has to do with the clutch assembly itself. I vote for a naughty bearing.

My noise comes about on decel from 2k/2500 all the way down to idle, and the noise is more prominent in 1st and 2nd gear

[ZenkiSilvia]

You're saying that the noise occurs from 2500 all the way down to idle? or between 2500 and 2000 on decel. If it's all the way from 2500 to idle it most likely is not the same issue i was having or flybert like others.

Ours was an issue with Decel between 2500 and 2000 RPMS in almost every gear (at least with me). Mine also does it on 1500 -2000 RPM's in 5th gear on ACEL. It's gotta be something with the load/disc/springs.

In your case I would check out the flywheel, or T/O Bearing. Realistically you should just look at everything or try removing and re-installing the driveshaft. Goodluck.

[EchoOfSilence]

mine rattles from 2500 to 2000 but it's a different sound. Stupid muffler shop welded a hanger to a hardpoint in the rear, and around that rpm range there's resonance so there's vibration.

well, good luck guys