I'm just about to crack 150,000 on my 1997 Z24 and the car still has it's original clutch and transmission. Other than a slight clunkiness going into gear if I'm not very well rev matched that's been there almost from the beginning, all appears well. I'm curious if this is par for the course with this motor as when I bought the car the finance guy tried to get me to buy the extended warranty based on the fact that the transmissions and clutches on these cars usually wore out around 60,000 miles. What's everyone else's experience? Anyone break 200,000 on the original clutch?

-Dirt-

Isuzu trannys have a weakness in the dif's spider gears. Someone somewhere has cryo-hardened ones to replace, but if the OE ones go, new tranny no question. Try aftermarket for a new clutch. I got a stage II from clutchmasters - nice improvement from OE without going all out racing. Your tranny is close to being wore out, I'm guessing. You won't need to upgrade the flywheel unless you have a penchant for performance.

I have a penchant for making the car last until 250,000 miles at least...

I have the same "clunkiness" you describe which just gets worse with lower temps. At about the 120k mile mark, my diff decided it was done. Luckily it did not damage anything else in the tranny, so $700 later I had a new diff and clutch. They actually told me the clutch looked pretty good still, but figured it should get replaced while they had it all apart.