people its all about the braking in period i had the same problems 2k miles ago i live in a city where there's always traffic i take my 370 to work and from every day i had my grinds all the way up to 1500 miles until i broke it in shifting all the time and ive noticed a few things, like to make an error shifting is very easy w/ this tranny u cant push the gears in too much without allowing it to synchronize 1st meaning if ur driving slow u must shift slow and if ur driving fast u may shift fast, if u force w/ ur hand the gear in too much ull grind and if u let go of the clutch too soon wile the gears are synchronizing ull grind, sometimes ull think that the gear is in but its really not its in the middle of synchrony and u let go of the clutch ull grind. All happened to me and all those where driver errors, but after 2k miles on it in every day in traffic it broke in and its much harder to mess a gear up not because i got better but cuz u can feel it broke in, its smoother, easier to go through gears, synchronous twist faster and they get in place faster and easier i can shift my gears around 1.7 k rpm without worrying that my synchronous will take a wile to align the only gear that still gives me trouble is my revere gear its the only one that feels stiff and yes i still grind it once in a wile when i dint pay attention (driver error).

Don't forget this one- http://www.the370z.com/engine-drivet...ing-shift.html

I did my break-in period until 3500 miles. I didn't experience my issue until 11.5K miles.

For me, the issues were with the 3rd and 5th gear.

Mine definitely grinds when entering 5th (see other thread). Still does it at about 16K miles now, although hasn't become much worse with the last 10K.

The problem occurs when upshifting 4-5 briskly. Ordinary non-spirited shifting is smooth. ALWAYS grinds when going from 2-5 (of course), even though shifts fine from 3-6.

Waiting a while before taking it in to dealer, but don't expect it to improve.

I grind from 6th to 5th downshifting occasionally, not an agressive down shift either. This transmission may have strong gears as they claim but the synchros are garbage.

I haven't had issues with any gear with the exception of 2nd. I would say 2 out of 10 times I get a smooth a transition (no jerk forward) when shifting from 1st to 2nd. It's like I have to be real particular with the way I lift my foot off the clutch and give it gas. Does any one else have 2nd gear issues? I don't know if it's a clutch issue, or just the nature of how it was designed.

Every 370Z I've driven has a very "crunchy" 3rd and 5th gear shift. Jnaut actually mentioned this to me a few months back as well. New tranny for it? thats amazing.

yes, the 3rd and 5th gears tend to grind a bit when entering them at lower speeds.