MT85 is not what you want in your diff.

 

I've Used both MT90 & MT85 GL4 with a vLSD diff. I change mine out every year. I only drive 1000-2000 miles per year on the Z but I have never noticed an issue. All of my miles are hard track time miles and nothing has come up.

 

When in my post did I agree with them that it was flywheel clatter? You on drugs boy? Holy hell..
And when did I say replace the flywheel? Stop making assumptions you retarded f*ck.

All I said was my friend had that noise, a few weeks later his flywheel went to sh*t so fix it before the OP's goes bad.

They seriously should look into having an IQ test before allowing people on the internet...

 

TA-DA! Telling the OP to get it fixed. There is nothing to fix

The sound the OP describes is a clean MT with no issues at all. You have no clue what you are talking about. Seriously.

 

You just done went full retarded.. I don't associate myself with ignorant people, peace n!gga

 

Bruno, I tend to agree both with myself and the others. The "your friend" argument and his situational failure does not supply any facts based on personal experience or causality. What year was that Z, was it a stock dual mass flywheel, was it aftermarket, Was the car modded or stock, what revision on the transmission, was your friend a complete tool who did not know how to drive a 6 speed. These are all questions that lack answers for your point to have any validity. I posted because my car makes what can be described as the same noise a flywheel chatter, I have 30K on my setup without failure, its a single mass lightened flywheel like the OP stated was added aftermarket if you can infer from the first post the information provided. This is a common issue, Occams Razor suggests that the most plausible answer is likely the most correct one. No need to quote movies to back up your unsupported theories, we use science and experience.

 

It is probably your throw out bearing. If you push the clutch in the sound goes away? If so, it is perfectly normal and will not harm your car. You can replace the TOB but from what I have read it is possible for it to come back in a relatively short period of time. It can wait until you need a new clutch and will not harm your car at all.

 

Thanks Everyone!! I appreciate the help and guidance!

 

oh **** thats a no no my man, you want GL-5 fluid in your differential. MT-85 and MT-90 are only for Manual Transmissions hence the MT and they are GL-4 for the trans, if you want Redline fluid in your differential 75W90 GL-5 Gear Oil is what you would want to use

 

Oh and OP welcome to the forum and congrats on the purchase, enjoy it. As for your concern, sounds to me like the good ol 350Z cement mixer flywheel chatter lol nothing to worry about. If you want to make it quieter I sugest when you start modding and get tuned tell your tuner to bump your idle to about 800-850RPM and trust me youll never hear it

 

When I read that your car sounds like a jet winding down when you slow down in first, and in second it's less, & 3rd., 4th nothing, tells me that you have very little experience with cars.

My advice would be the same as Redlines. IGNORE everything! Get some more knowledge, (like maybe you shouldn't put a car in 1st gear at high speed), and enjoy the car.

You have a great car, so enjoy it. It's stupid to replace things that may not/are not broken. Putting the radio on louder might help.