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So my standard clutch finally gave up so purchased a lightened flywheel and a 6 puck clutch kit. Installed it all last weekend, the only thing not replaced is the bush inside the crank as I was running out of time. Everything has been bolted up correctly, surfaces checked, there was a little bit of machining material left on flywheel dowels but cleaned it all up so the pressure plate definitely sat flush. Gearbox was supported the whole time so clutch shouldn't have bent, there's no judder/shudder and car drives fine.

Been driving the car easily to get everything to bed in so haven't pushed it yet but have noticed that more vibrations are coming through the car, especially at around 4k rpm mark where it starts to gets a bit crazy.

I have solid mounts for the gearbox and in the subframe, a bit more noise came through but no biggie as I've been using them for over a year.

At first I though it could be the driveshaft being unbalanced but it also happens in neutral at around 4k rpm there a big vibration starts coming through the car, which keeps increasing as the revs go up. The vibration is of high frequency, as if something is out of balance slightly.

I can't feel this vibrations on the clutch nor through the shifter.

Anyone experienced something similar after a clutch job? Any tips of pin pointing the location of this vibration?

Edited by ErOR

Did you mark the driveshaft flanges before you separated them, then put them back at the same orientation? If not, try disconnecting, turn through 90 degress, then reconnect.

Did you mark the driveshaft flanges before you separated them, then put them back at the same orientation? If not, try disconnecting, turn through 90 degress, then reconnect.

Agreed, try this first something about them being balanced. I put an exedy kit in my car and don't have an issue (flywheel and cushioned clutch plate)

The clutch is from a reputable store in NZ, not actually sure on the brand or where it came from. The gear is definitely of high quality, could be a bad batch. Will go see the guys there today and have a chat about it.

No I didn't mark the driveshaft flanges but remember this vibration is happening in neutral, driveshaft shouldn't have anything to do with this vibration as far as I know.

I'm leaning more towards pressure plate cast being out of balance or something similar.

So your saying a drive shaft that is physically connected to the diff and wheels doesn't spin in neutral?

Check again young grass hopper [emoji106]

Do these vibrations come if the car is sitting still and you rev to 4K as you mentioned that's when it's worse?

Edited by Gcjosh

So your saying a drive shaft that is physically connected to the diff and wheels doesn't spin in neutral?

Check again young grass hopper [emoji106]

Do these vibrations come if the car is sitting still and you rev to 4K as you mentioned that's when it's worse?

Only the engine, flywheel and pressure plate spin when in neutral. Clutch plate, input shaft, driveshaft etc are still.

Sorry OP - I didnt read carefully enough and missed it was in neutral. So agree it sounds like out of balance flywheel or pressure plate.

If it happens when your stationary test it with the clutch pedal in and out, if its there in both situations id be getting the flywheel and pressure plate checked for balance.....

  • 1 month later...

After the 6 puk melted to the flywheel I got the flywheel and pressure plate balanced and all the vibrations are gone now.

Lessons learned, experience gained...

Also switched from ceramic to kevlar and it's so much nicer to drive around streets, 6 puk ceramic can stay for the track.

Edited by ErOR
  • 3 weeks later...

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