Ok, so I have a few days off, it's not raining and the roads are free from salt/grit.

 

Took the zed out for a spin. For the first, maybe 1/2 a mile, the gearbox sounded like it was totally shot, but suddenly it cleared up.

 

Now, it does crunch in second when it's cold, other than that, it's a nice gearchange.

 

Does it sound like it needs some replacement oil?

Mine does this too and I'm also thinking oil change time soon !

most peeps with manual trans use Redline mt90 it cures minor probs, whinning/syncro related.

Just put mt90 in mine after a clutch change & cant believe the differance in noise level as well as smoothness. Would deffo recommend in Simon.

Mine's a lot smoother since oil change (nothing fancy just what partco recomended to me) and the 4th gear syncro crunch seems to have cured - cool! Still hard to get 2nd when cold but a lot of cars have this problem - 2 mx5's i've had, Mr2 - only 2nd - weird!

http://www.300zx.co.uk/forums/showthread.php?t=60211&highlight=gearbox+oil

manuals that whine,is usualy the 2 gators that sit over the linkage,they tend to split,therefor you hear road noise from the transmission tunnel,worth a look,thats what happend on mine