clutch slipping during track days
 

Not sure why my clutch is slipping at 29K miles, but my car definitely can't go from 2nd to 3rd quickly without a long slip or really slowing the shift down. It would even do it from 3rd to 4th from time to time. Has anyone run into this problem yet? What are good reliable clutches at stock power?

THanks

Can you give a more detailed explanation of exactly what you are perceiving?

29K seems really early for a clutch. A much more common problem is with boiling clutch fluid/slave cylinder failure/master cylinder failure (I know that I have had all 3 fail at the track).

I also know each time I brought my car into the dealer they tried to sell me a new clutch. I had to insist that I knew my clutch was fine. I can only imagine how many clutches Nissan/Infiniti have sold after misdiagnosing burnt up clutch fluid.

Can you stall your car starting in 3rd gear? That's a fairly accepted test of a clutch.

Don't be too alarmed...my dealer was recently changing my short block and told me my clutch and flywheel should be replaced.... I'm at 26k, and have never been to track. I baby the car for the most part. I haven't had issues with it yet, but I am expecting to now. I have never changed a stock clutch so soon before.

Please explain the stall in third gear for me. I've not heard that one before, and would like to try it.

The idea is if your clutch is still good the car should stall when trying to start in 3rd. If your clutch is bad and slipping it will not stall.

If you do need a new clutch there are lots of options. If you are going to replace it you may as well do a fly wheel as well.

I have heard a lot of good things about the Jim Wolf Technologies Combo.

most likely you do not need a new clutch, but later if you do, call Joe at Zspeed and he will hook you up!!!!
I had the csc fail on me TWICE, upgraded to Zspeed hd csc and a new oem master.

Odd its slipping so early. I'm at 70k with a lot of tracking and no slippage

Do we have a terminology problem here. It sounds to me like the clutch is not dis-engaging drive when the clutch pedal is fully depressed which is what makes the shift "slow and/or difficult".

A slipping clutch says to me that engine revs rise and speed does not rise in proportion so the clutch is not effectively engaging drive as the friction surface on the drive plate is worn excessively.

A dodgy CSC on the other hand will not disengage the clutch making shifts difficult and/or slow. This can be variable if the fluid becomes excessively hot - and the pedal function returns when it cools.

Can the OP confirm the symptom more clearly because if the issue is having to spend a lot of time with clutch pedal fully depressed, that sounds like a CSC or fluid issue rather than a slipping clutch.

Before changing the CSC, simply replace the clutch fluid as step 1.

Sounds like your CSC, which is more or less an inevitable replacement on the Z.

Same here, knock on wood.

im going to Buttonwillow next weekend, if my clutch slips, i know i spoke too soon LOL.

Basically if I come off any slow corner in 2nd gear. If I try to shift quickly into 3rd, it's almost a given that the RPM will just stay in the 7000RPM. It would eventually catch and slip into gear. It would do that from time to time going into 4th too.

CSC or clutch, both sound bad as they both require transmission removal. I guess at least I will fix the stupid bearings that are noisy

Sounds like it. My diff was a pita on my garage floor. I don't even want to think about the tranny.

Sounds like a fluid/csc/cmc issue. What is happening is you are running to 7000 in 2nd gear and when you try to shift (depress the pedal) your clutch is not disengaging thus your rpm's are staying as if you were still in 2nd (because you are still in second).:twocents:

The good news is that your clutch is probably fine and slave cylinders and master cylinders are covered under warranty! Just don't let them bully you into purchasing a clutch (b/c not covered under warranty) or god forbid using GT-R clutch fluid at $150 per bottle (they tried that on me and I really had almost yell at the service tech).

the GTR fluid is 49.99 a quart from nissan. not $150

I believe this also included labor for a TSP on the clutch.

Regardless, I do appreciate the absolute insistence of accuracy whenever posting on this forum.

I use castrol srf, it's as good as it gets. I guess I just have to deal with this until I pony up to take the trans out

I also only use SRF. Liquid gold and worth every penny.

Yes but I swear I still get fade with them on my brakes

One thing I read with the higher temp fluids is that they suck up moisture from the environment much faster than the lower temp stuff. When was the last time you replaced the fluid, not that cali is a very wet/humid region?

:tup:

would you rather have misinformation?

My clutch was slipping at 35k. Bought it used with 22k. I'm guessing the previous owner didn't know how to drive stick, or beat the balls off the clutch. Called in a favor at Nissan and had it covered under warranty.

wow! lucky guy!

stay friends with that dealership. haha

Yeah, got lucky with that one...

UPDATE.....
3+ years, and 30k+ miles.... Stock clutch still going strong. Hmmm. maybe the dealer was trying to get me for $1800????:rofl2:

This isn't a fluid issue. I had this happen with RBF600 on the street and strip. Definitely CSC related. It's just not putting enough pressure on high rpm shifts. It feels similar to a weak clutch, but it only happens when shifting at high rpm. I replaced everything instead of guessing what was what. I have the SpecialtyZ clutch and flywheel now and it's been outstanding. No more slipping.

More than likely it isn't your clutch, but your csc going out. I had the same issues as you're describing and when i replaced my clutch come to find out the flywheel and clutch are in really good shape.

Also try flushing your clutch line and replacing it with brand new fluid, then go recheck it in and month or two. If it dirty again then its probably your csc going bad or master.

bad clutch fluid / CSC shouldn't cause clutch to slip because since pressureplate is mechanically back to it's original position which is engaged to the flywheel regardless when pedal is not pressed. fluid/csc should only contribute to clutch disengaging from flywheel so in the case of bad fluid/csc/mc, you would only have problem disengaging. my guess is that pressure plate is bad, or clutch is unfortunately burnt. i've had bad pressure plate which the teeth ended breaking off, and had the same symptom of slipping before eventual failure.

The most common causes for a clutch to slip. Now you have to play Diick Tracey and find out the real cause.

1. Worn clutch disc. Disc too thin for proper pressure between the flywheel and pressure plate.

2. Weak pressure plate springs. Could be from overheating from too much slipping the clutch pedal or linkage adjustable.

3. Leaking slave cylinder. Fluid on disc and pressure plate.

4. Mis-adjusted linkage. Not allowing the slave cylinder to fully retract. And causing the unit to overheat.

5. Hot spots on the flywheel and pressure from riding the clutch pedal, and from the things listed above.

6. Mis-match parts.

7. Driver error. Riding the clutch pedal. The hardest one to prove. Everyone will denied it. :icon14:

These are the most common causes that I have run into over the years.

Caused mine to slip. Installed new twin disk and looked over the clutch and it was perfectly fine, no hot spots on the clutch or fly wheel

Hmm..

The winner is... #7:nutswinger:

I was able to work around it by swapping the clutch fluid (I didn't do a full bleed, I just suck out the reservoir and put in high temp castrol fluid), problem stopped.