Just as the title says, I was experiencing really bad clutch slip, I have an 05 G35 coupe Revup with 95,000 miles. I ordered up a Z1 mild performance 6 puck clutch along with a mid weight flywheel. Dropped the trans, and as expected it was the OE Nissan clutch and FW. Now I’ve never done a clutch so I’m gonna drop some pics of them. Tell me what you guys think, is it bad? The clutch don’t look terrible to me.


Another thing, I noticed when doing hard shifts my clutch pedal would get stuck at about half-way up in the release throw. I also played with the clutch fork after I removed the CSC. Even with the CSC disconnected, when I push the clutch fork to the left, it would only rebound about half-way back to the right. I have a new throw out bearing and pilot bearing/bushing to be installed with my new clutch kit, hoping that solves the issue.

Edit: lmk if I need to zoom in the pics for u guys, seems it might not work well on this site for you to zoom it in by yourself.

 

Probably need to bleed the clutch fluid if the pedal is sticking. Pay close attention to the orientation of the little wire spring that holds throw-out bearing carrier to the clutch fork.

I STRONGLY recommend replacing both the clutch master and slave cylinder when doing a clutch job, the components all wear out at about the same time.

6 puck is going to be super aggressive, that is definely not a "mild" clutch, full face is mild and all you need for an NA engine, sprung hub for a daily driver, unsprung for a racecar.

 

When I say mild clutch, that’s literally the option I picked on Z1 website. There’s a mild performance option, or street performance I believe. It’s a sprung hub 6 puck. I’m drifting this car so wanted more aggressiveness to it. If it was clutch fluid wouldn’t the clutch fork rebound to its original position? The fact that when I had the CSC completely off and the fork wouldn’t fully rebound made me think the issue lies inside the trans

 

I've ordered quite a few of the Z1 clutch kits, the 6puck is an option, the standard clutch is a full-faced but if you're planning on going FI for drifting then it's fine going with the 6 puck just know that it's definitely not getting 100k out of that clutch, they're good for MAYBE 80k as a daily driver. This might be perfectly fine for you though. The mild or performance option is for the PRESSURE PLATE, not the clutch friction disk, you definitely want the mild pressure plate unless the car is making over 400whp, the performance one is VERY stiff.

Back to the issue about the clutch fork, unbolt the slave cylinder, then remove the rubber boot so you can see up inside the bellhousing (you can put it back on later, a small screwdriver helps to push the rubber around properly). You will be able to see the entire assembly with a flashlight to verify it's working properly. I'm very suspicious about any issues with it not resetting to the correct position because the pressure plate WILL push it back where it needs to be unless the wire spring for the carrier is put on upside down, here is a picture of what it's NOT supposed to look like. The spring is supposed to have it's little "half-round wings" pointed up over the top of the fork, not down on the fork".




The slave cylinder will not be FULLY compressed when the clutch is not engaged, there is still quite a bit of play on the CSC so you will be able to grab the clutch fork and push it over to the left. It's neutral/resting position should be right at the point where it's just barely touching the pressure plate.

The reverse hydraulic pressure generated from the pressure plate pushing back on the slave cylinder when you release is what's pushing the pedal back up past it's fulcrum point (where the spring on the pedal kicks in and snaps the pedal fully up). If it can't even make it to the fulcrum point then either there is air/water in the clutch fluid, or the CMC/CSC are worn out, or the clutch line is bulging, or the spring is put in backwards on the TO bearing carrier, or the clevis pin attaching the clutch pedal to the master cylinder isn't "floating" with no pressure in either direction when the pedal is in the full up position.

Don't just go off the measurement for the CMC rod length in the FSM, you still have to make a minor adjustment to make sure that pin floats in the bore on the clutch pedal.

On a new clutch you should start to feel engagement almost literally as soon as you start to lift your foot off the pedal.

With the vehicle on jackstands you should be able to push the clutch in fully, tap the brakes, and the wheels will not continue to turn. If they DO still turn then the clutch isn't fully disengaging, thus not delivering a full stroke of pressure back to the pedal to push it past it's fulcrum point.

 

Here is the correct orientation of the spring on the carrier bearing housing. Having it backwards like the previous post will DEFINITELY cause issues with the pedal not returning. You can see the spring by removing the rubber dust boot over the clutch fork.

 

I have the transmission out of the car right now. So I’m gonna disassemble the clutch fork assembly and clean, replace bearings, and reassemble. Any word on good master/slave replacement parts? I think I might hold off on slave as that seems it should be pretty easy to replace with the trans in the car? Idk I’ve never done a slave or master. This is just a budget build and I don’t wanna throw unnecessary money at the car. I’m sure the clutch should have lasted a lot longer. Car only has 95,000 miles and it’s been bone stock its whole life. I just think previous owner wasn’t very experienced driving MT. Didn’t seem to kno jack about the car while speaking to him. Anyways, the clutch is what I believe to be from factory. It’s a Nissan clutch and flywheel, so I don’t believe it’s possible for the pin to be installed incorrectly. Previous owner stated he never changed the clutch and had the car since 60-70k.

 

Ok I thought you had the clutch pedal not return on the NEW CLUTCH. If the system is 100% original it's probably just due to age of the fluid, it picks up a LOT of moisture over 100k miles and since the clutch line runs very close to the headers it's easy to boil the water when driving hard then the pedal sticks halfway down.

However you SHOULD always replace or rebuilt the CMC and CSC when you put in a new clutch since they definitely will not last through a second clutch and when they die they can take out the clutch with it (pedal sticking halfway spins the clutch pretty hard, very easy to smoke the new clutch).

The OEM rebuild kits for the CMC/CSC are pretty cheap, I would recommend doing that.

Word of advice, do NOT bench bleed the clutch master, it's impossible to get the CMC back into the car without getting brake fluid on everything, it's extremely tight working spaces inside that box with the brake booster. Much easier to just install it empty and gravity bleed most of the air out of the system once everything is reinstalled, then start doing traditional pump/bleed after you've gravity bled out all the old fluid and it looks new again. Just be prepared that you will almost definitely need to wash out the brake booster box with brake cleaner and a lot of water because even dry it's practically impossible to change the CMC out without dripping fluid on the paint inside the box. Just be careful about not using pressurized spray because you should keep the ABS relay and harnesses dry. FSM steps have you install the CMC dry, I've done it both ways a couple times and will always install them dry from now on because you get brake fluid on EVERYTHING, it drops down the fender well at the brake box and gets all up inside various metal pieces of the unibody and ends up dripping out down near the middle of the driver door. Not worth the hassle compared to bleeding a little extra air out of an incredibly small chamber inside the CMC.

You can also use a motive power bleeder with the small universal adapter, unbolt the CMC reservoir and stick a small piece of wood or something under it to get the chain around it properly. That's my preferred method.

I also very strongly recommend replacing the clutch line flex section that goes to the CSC.

As for the dowel pin, if it's all factory untouched stuff right now it's probably fine, but you will have to make a very small adjustment once you install a new CMC even an OEM one. It's easy though, there is a jam nut on the shaft of the CMC on the inside at the pedal, loosen it and then rotate the CMC shaft to screw it in/out until the clevis dowel pin is floating in the clutch pedal, then hold the shaft with a small pair of channel locks or pliers while you tighten up the jam nut again.

 

Sounds like I’ve got quite a bit more work on my hands than I anticipated.. I did order up a SS clutch line from Z1 along with the clutch kit.

 

The good news is you can do the CMC and CSC later at your convenience. The rule of thumb of clutch replacements is to drive easy on the car for the first two tanks of gas before laying into the throttle.

I wouldn't put it off for a year but as long as you get it done sometime THIS year (or definitely before the next drift event) I think you'll be fine, just make sure to flush out all the clutch fluid when you're doing the clutch job though since you've already had "pedal not returning" issues. The valvoline synthetic DOT 3/4 fluid is excellent for street use and very cost effective. Switch to the expensive Motul fluid later when you swap/rebuild the CMC/CSC.

Puck clutches can he broken in quicker but if you have the time I would be easy on the first couple hundred miles. Especially if you're trying to daily drive the car and get the most life out of the clutch.

 

I’ve been back and forth about doing the CMC and SC. But oreilleys has em in stock with lifetime warranty. So I’m grabbing those today after work and probably get started throwing them in tomorrow after work. I’ve read about using Motul for the clutch as well as GTR dot 4. As for the trans fluid I’ve seen people use genuine oem and others say Motul for trans fluid I believe. What u think about those? And yes, i was under the impression I should break in the clutch for 300-500 miles before letting her eat.

 

I'm sort of a fanboy for Nissan OEM components so I can't speak to the quality of the O'Reillys CMC/CSC but they're probably fine, things like this are usually OEM equipment that's been rebuilt with a new seal kit and it's kind of hard to **** up 2 o-rings (that's literally all there is to rebuild inside) so you should be fine with them. You could just rebuild your existing ones, it's SUPER easy and costs about $50 plus shipping for the OEM rebuild kit for BOTH components. Literally just depress the retention plunger, pop out the captive pin or circlip, gently release the plunger and not shoot the spring across the room (it's not that much pressure, just be aware it's under a little pressure from a spring), then put the new one in (use a little brake fluid to lubricate the bore and o-ring), put the capture pin or circlip back in, done.

My previous CD009 was starting to show a little synchro wear so I was running Redline MT-85 or MT-95 (whatever they had in stock at the time) in it which worked great to smooth out the shifts again. My new CD00A I just run Valvoline synthetic 75w90 because I'm a big Valvoline fan and it's always in stock locally in VAST amounts.

As for the clutch fluid, I run the Valvoline synthetic DOT 3/4, something to keep in mind is that those really high end fluids like the Motul 5.1 are designed specifically for RACECAR APPLICATIONS, things like professional race environments, Nurburgring and stuff like that. There's a REALLY REALLY good chance you don't need fluid that extreme because you're not generating that much heat from the brakes/clutch.

Regardless which you decide to use the most important thing is to replace your brake/clutch fluid every year if it's being tracked at all, or every 2 years for a daily driver street use (miles doesn't matter, every 2 years it's absorbed enough water that it's near 3% water or higher). Transmission/differential gear oil every 20k miles if the vehicle is being tracked at all (good rule of thumb is change it once per year unless you're actually putting that kind of miles on the vehicle) for normal daily driver every 30k miles.

 

Yeah I mean I too normally would only buy OEM products, like I’ve done previously in my old g35x and my current g37x. However like I stated this is budget and the store has them in stock and I don’t have to wait for shipping. They also got lifetime warranty so if it ever breaks I’ll just get a new one for free. Can’t be too bad of a deal.

 

Go for it, lord knows I've bought plenty of O'Reillys parts since they're the closest parts house to me.

 

Amen. I’ll give it a go. Thanks for all ur advice on all my posts u da man!

 

Yo so I tried getting some MTF from my Nissan dealer and the only thing they had was some 75w-90 axle oil and some 75-85w rear axle oil... nothing that states mtf on it... so is the 75w90 axle oil what I need for my trans? Back of the bottle said it contained gear oil