Thanks for the tips. I couldn't resist a low miles (28.5k on an '05) unmolested z. Epstein, the door sticker is '04, so I wonder if I got the questionable tranny. It seems ok, but how would I know which version I have? The noisy front end is probably the oem tires, but has anyone heard of early wheel bearing failures? Also some engines have oil consumption problems but hopefully not my version.
Other concerns are the 6 spoke touring wheels (aesthetics) and the cd changer which doesn't play mp3's. I'll check with the audio experts, but preliminary research indicates the Bose stuff is somewhat incompatible with aftermarket gear such that it's all or none on upgrades.
Noisy front end is the tires. Mine does it, too. The tires will wear a certain way as they get old, and that makes a ton of noise below 20mph. It's something to do with the alignment, crazy constant-caster geometry, and bumpsteer.
Nissan released a ton of different versions of the 6speed. The feb 05 date that I quoted is an assumption. I know the final version was in the 05 Track and AE, which were released later in the model year. And I know that the earliest build dates on those models are Feb 05 because my father had one on order 5 months before and got the first one locally. If you want to be sure, look for a little sticker on the tranny bellhousing that says CD00#, # being the trans version. CD009 is the last version. Or, if your trans shifts fine, then don't worry about it. People were returning the early ones in the first year.