Horrible rattling/vibration noise in 3rd gear in higher RPMS

babyzilla · 07-02-2020, 09:12 AM

So...I had a similar issue and was never able to pin point the problem. It occurred at high RPMs in all gears for me. Although it didn't sound good at all, the car seemed completely fine, so I never bothered with it (just thought it was another quirky issue with the Z). Then I had the dreaded CSC failure and replaced the clutch and master/slave cylinder. The noise has completely gone away and drives better than the day I bought it.

I think we can agree it is a transmission issue. I have a feeling if you make the same changes I did, your issue will go away. I'm just not sure if it's the CSC or clutch.

SouthArk370Z · 07-02-2020, 11:19 AM

Quote:

Originally Posted by tibor370

... was told that the transmission mount is the most likely culprit ... should be replaced. ... only done 22,000 miles but it's almost 10 years old. So maybe the rubber mount deteriorated over time?

Very possible, especially if the car gets driven hard (sounds like you don't baby it). They tend to get hard over time and can shrink a bit - the looser fit plus the harder "rubber" can lead to Noise, Vibration, and Harshness (NVH). Could also be caused by one of the other drivetrain mounts (eg, the differential bushing which has a tendency to rupture).

Quote:

Originally Posted by Spooler

It sounds like the shifter knob vibration. Do a search on here. There is a fix for that.

I'm too lazy to look that up but Spooler seems to know his stuff, so I'd look into it if it were my car.

Quote:

Originally Posted by s2krazyyy

I had this issue where vibration was present at high rpms. Try pulling off your shift knob/boot and pull up the rubber part under it. I pulled mine up and ziptied it so it wont sag down, it got rid of my vibration.

Worth looking into.

Quote:

Originally Posted by babyzilla

So...I had a similar issue ... had the dreaded CSC failure and replaced the clutch and master/slave cylinder. The noise has completely gone away and drives better than the day I bought it. ...

Another possibility to look at. 370Zs are infamous for CSC failures and other clutch issues.

I'd first look into what Spooler and s2krazyyy suggested; mounts, bushings, and clutch parts are pretty expensive and not that easy to fix even if you have a well-equipped shop.

Edit: First thing I'd do is change the transmission fluid. There are several threads about which brands, weights, etc to use. Might as well change the diff fluid while you're at it. Probably won't cure the vibration problem (still a very small chance it will), but needs to be done if you still have factory fluids.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Slight vibration at higher speeds	Troglodyte54	Wheels & Tires	7	02-15-2019 04:38 AM
rattling noise during 1st gear	ShockWave	Engine & Drivetrain	43	10-02-2016 05:30 PM
rattling at high rpms	seanjkline	Audio & Video	2	05-07-2013 09:54 AM
HORRIBLE NOISE! Screeeeeching...	Hugoneus	Nissan 370Z General Discussions	16	09-17-2010 04:40 PM
Higher gear ratios	Zeto	Engine & Drivetrain	8	07-09-2010 08:37 AM

07-02-2020, 09:12 AM	#1 (permalink)
babyzilla Enthusiast Member Join Date: Apr 2017 Location: Maryland Posts: 487 Drives: 15 Nismo Tech 6MT Rep Power: 23633	So...I had a similar issue and was never able to pin point the problem. It occurred at high RPMs in all gears for me. Although it didn't sound good at all, the car seemed completely fine, so I never bothered with it (just thought it was another quirky issue with the Z). Then I had the dreaded CSC failure and replaced the clutch and master/slave cylinder. The noise has completely gone away and drives better than the day I bought it. I think we can agree it is a transmission issue. I have a feeling if you make the same changes I did, your issue will go away. I'm just not sure if it's the CSC or clutch.