CSC or CMC problem?
 

I've done some research and it sounds like I might have one of these issues. These past couple weeks my clutch has felt different. Sometimes It'll feel like there isn't much pressure when I press down on the clutch. But that's ONLY after running it hard. Normal driving it's completely fine. So last night I ran it hard and right after I stopped and I tried pressing down on the clutch and it wasn't engaging!! It didn't want to go in any gears. I pumped the clutch with my foot and it eventually engaged into gear again and pressure came back and I drove normal the way home and it drove fine again. I think I might just need to change my clutch fluid or do I have a part that's on the edge of failing?

Kind of sounds like you are boiling the fluid. I think a change of fluid, upgrade to a higher grade fluid, and consider heat sleeving the clutch line that runs by the drivers side exhaust manifold (or upgrade to a pre-sleeved stainless line).

That's not CSC failure, not to say it isn't on its way out, but no failure yet. When mine went my clutch pedal would literally stick to the floor board and I'd have to pop it back up with my foot.

Have you seen any black particulates floating in your clutch fluid reservoir?

What type of fluid would you recommend?

Okay well that's good to hear. Seems like all of us Z owners have to change our CSC at some point based on what I've read. Seems like Nissan needs to come out with a recall on it from all the issues... and I don't see any of that in the reservoir but the fluid has a blackish/brownish look to it

That black/brown fluid is telling you that you are way past your fluid change interval. You need to do a gravity bleed and get all that nasty out of the CMC reservoir. Recommended fluid would be Motul RBF600. You can change it out with Castrol DOT 3/4 brake fluid if you are in a pinch.

I just got it done like 4000 miles ago. I didn't think it'd need some again that soon. Or I wonder if they just used a crappy brake fluid

If the fluid is discolored, I would certainly recommend bleeding the system and replacing the spent fluid with a high quality DOT 4 brake fluid such as Motul RBF600 or equivalent. The loss of pressure could signal that you were boiling the fluid. It could also suggest that your CMC is on its way out. As indicated above, if the CSC fails, the clutch pedal will normally stick to the floor and there will be signs of fluid loss (... either fluid visible under the transmission bell housing and/or a drop in fluid level in the clutch fluid reservoir). If the CMC fails, the clutch pedal will often feel "soft", but sometimes will recover by pumping it a few times. For further advice, you may want to contact Joe at Z Speed Performance and/or Ryan at RJM Performance. They both have a lot of experience with the problems associated with the stock clutch system.

Yeah I'm gonna make an appointment tomorrow to bleed the system and replace clutch fluid. How many bottles of motul 600 will I need? Can I buy this stuff locally? I called around and not many people carry it. I will probably need to change my CSC and CMC sometime. But I'll just keep that in my future plans.

Also will I be fine driving it with dirty fluid for now... I could probably get all this replaced Tuesday or Thursday this week

The Motul RBF600 comes in a 500 mL container. One container should be sufficient ... but you may want to buy two just to be sure. You can always keep any extra for future use ... especially if the container has not been opened. (The fluid is very hydroscopic and will attract water as soon as the container is opened. The boiling point of the fluid will drop as the water content increases). You should be OK driving it with the dirty fluid for a few more days. Whatever's happened, has happened. I doubt things will change over the course of the next couple of days. Is there any evidence of fluid loss ... or is the fluid just dirty? You may want to snap a picture and send it to Joe at Z Speed and ask for his opinion.

The fluid basically just appears dirty. The fluid level seems fine. It's between the min and full mark. I will prob hit him up and see what's going on

Most likely crappy fluid. If it has ever been neglected, it will take 3 to 4 fluid exchanges to get cleaned up. I change mine ever other oil change.

i bought 3 500ml bottles of motul 600 to be safe. That should be enough for a bleed and replacement right?

Probably enough to do it 5-10 times. =)