High Mileage 370z Reliable?

vtec to vvel

It's inside the housing bell of the tranny.

FWIW, alot of members have had issues with the Z1 kit, and will recommend ZSpeed.

40 to 332

This. As indicated, the stock concentric slave cylinder (CSC) is located in the transmission bell housing. If you elect to replace it, the transmission will need to be dropped. I would recommend replacing it with the Z Speed CMAK kit, which places the slave cylinder outside the transmission ... meaning that if it ever fails in the future, it is relatively easy to replace without need to drop the tranny. That said, I'm not aware of anyone who has reported problems with the CMAK slave, and the kit has been on the market for several years. Also, if you decide to replace the stock CSC, you should seriously consider replacing the stock clutch master cylinder (CMC) at the same time. It is also prone to failure. In addition, if you want to virtually bullet-proof the clutch hydraulic system, you should consider replacing the stock clutch pedal assembly with the RJM pedal assembly. Like the CMAK kit, it is a proven improvement over stock. Finally, if you gone this far, you might consider substituting the OEM CMC with the Tilton heavy-duty clutch master cylinder that is also available from RJM. Both Z Speed and RJM offer great after-market service and advice. You should reach out to them for advice on how best to proceed.