i bought my 04 350z a few months ago, it currently has about 80k miles on it. I was wondering how to tell what shape the tranny is in. When i am driving in 2nd or 3rd and when i let get off of the gas my car makes a noise (kinda like a whining noise) when im slowing down its like something is forcing it but once i am going slow enough in that gear it stops and slow down smoothly. Is it normal for the car to be noisy like that?

 

The transmission in our car is known to be a bit noisy

 

No amount of words can explain... Best method is to go to a Z meeting and get an experienced Z driver to drive your Z and tell you if there is something wrong or not.

 

alright well i just went for a little test drive with no music and windows down and every gear shifted smoothly the only thing i noticed was that shifting from 1st to 2nd at 3k was fine but when around 5k+ it felt a bit notchy not really a grinding sound but pretty stiff feeling and when downshifting from 3rd to 2nd it definitely sounded like it was grinding a little could this be a big problem or is this somewhat normal?

 

If you grind at the same spot, even with proper shifting, then your synchros are going out. If you need to stay on the clutch a few seconds longer to keep it from grinding, your synchronizers are going out.

I have this problem with my 300ZX going to 3rd, but it shifts fine if I stay on the clutch a few seconds longer.

 

if your synchros go out how much is it to get them fixed ?

 

You'd probably be better off to get a new transmission or a low-mileage unit with a guarantee from a wrecked Z. Replacing the synchros is a big and time-consuming job that involves removal and complete disassembly of the transmission.

I'd guess around $700, but that's just a WAG.

 

I'm having this same exact problem with third gear as well, would you recommend buying a whole new transmission or just replacing the syncro? Is it possible that I could go to a junk yard and just get the syncro itself rather than trying to grab the whole transmission? If I do replace the syncro what's the life span lookin like?

 

look into the labor to replace it... just buy the cd009 and be done. you will need it trying to get your 250whp car to 400 na

btw, you responded to a post from 4 years ago

 

Here I go again: before you try doing anything else, do a simple gearbox lubrication swap. Redline MT85 has the correct viscosity for our gearboxes and has just enough friction engineered in for a synthetic lubricant to allow the syncros to function properly. I use it in both my street and race Zs, and it makes a difference.