Jim 'n' SC

So I had a new clutch & flywheel installed (sachs). The flywheel makes a loud whining sound every time I shift & let out the clutch. Also, makes a lot of nosie when decelerating. Also has a vibration around 3,000 RPM.

Mechanic seems to think its normal. Its been 10 years since I've owned a 986, but I don't remember it making all this noise.

Macster

Unlikely the flywheel is making the noise. More likely the release bearing. Was the release bearing replaced along with the other clutch hardware?

Best get the car back to the shop that did the clutch. Almost certainly the transmission will have to be removed and a sanity check made of the work done. The work doesn't have to be bad though. A new release bearing properly installed can suffer from premature failure.