QUOTE (ogllandman @ Jun 11 2008, 02:22 AM) index.php?act=findpost&pid=534916
Do I need new syncros? (spelling?)
I've had my gearbox pulled down recently since I broke 3rd, and I've got some bad news on that front.
The Nissan service manual for the 350Z gearbox says that anything pressed out of the gearset has to be replaced with new items. That means any cog you press out needs to be replaced, plus all the synchros, plus everything else holding it together.
If you replace all your synchros, you'd basically be replacing your entire gearbox anyway. You could choose not to replace used parts as per the service manual, but Nissan would have put that in the manual for a reason and the cost of failure on a dead box could be quite high.
I'm not sure if replacing your clutch is going to fix your shifting issues (if its only 3rd gear causing it), but doing your clutch is a lot cheaper than doing your 'box. The random noises could be clutch noises instead.